DESPERATELY NEED HELP! WONT START (long story/brief explanation)

failsafe for temp.

i have never heard of our trucks having a fail safe with the oil system ie low oil presure or low oil level and it shutting the truck down to save the motor.
(added 11/20. It may have been my Coolant Temp idiot light, but this does not change the fact that my engine did shut itself down to avoid damage).
I know there is a failsafe for A/T oil temp. A few months ago I had dealer top off my coolant reservoir. Filled it to 'full' line. Drove about 5 miles, car stalled. Automatic transmission fluid temperature warning light was on. Wouldn't start. A few minutes later it started, warning light off, drove 10 blocks, shut down again, warning light on.
Googled and found posts about an over-full reservoir triggering this reaction. Don't remember if it just triggers the sensor or if it actually causes an overheating situation. Res. topped off causes level to rise above 'full' line as coolant heats up and expands.
Removed 2 or 3 or whatever inches of fluid from the reservoir, had Advance Auto reset OBDI. All is well.
This was before I installed a separate tranny cooler, so coolant and AT fluid shared the same radiator. Wonder what would happen now with separate coolers?
 
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I know there is a failsafe for A/T oil temp. A few months ago I had dealer top off my coolant reservoir. Filled it to 'full' line. Drove about 5 miles, car stalled. Automatic transmission fluid temperature warning light was on. Wouldn't start. A few minutes later it started, warning light off, drove 10 blocks, shut down again, warning light on.
Googled and found posts about an over-full reservoir triggering this reaction. Don't remember if it just triggers the sensor or if it actually causes an overheating situation. Res. topped off causes level to rise above 'full' line as coolant heats up and expands.
Removed 2 or 3 or whatever inches of fluid from the reservoir, had Advance Auto reset OBDI. All is well.
This was before I installed a separate tranny cooler, so coolant and AT fluid shared the same radiator. Wonder what would happen now with separate coolers?

Nope no safety measures there either... This truck is useing 20 year old technology... There are no fail safe measures... The only thing remotely like that would be the non interference motor. Again you are talking about technology that high end cars such as BMW, Mercedes, Audi, and the likes have only started implementing in the last 5 year's... They have also tried thever best(and done very well at it) to make their cars dealer only serviceable.

You got something else going on there. No way will topping off a coolant reservoir overheat your trans... That even defies logic, let alone reality.
 
round 1

Nope no safety measures there either... This truck is useing 20 year old technology... There are no fail safe measures... The only thing remotely like that would be the non interference motor. Again you are talking about technology that high end cars such as BMW, Mercedes, Audi, and the likes have only started implementing in the last 5 year's... They have also tried thever best(and done very well at it) to make their cars dealer only serviceable.

You got something else going on there. No way will topping off a coolant reservoir overheat your trans... That even defies logic, let alone reality.
(added 11/20. It may have been my Coolant Temp idiot light, but this does not change the fact that my engine did shut itself down to avoid damage).
OP's 2002 is 11 years old. My 1999 is 14 years old. They are not limited by 20 year old technology.
I understand what you are saying.
I am correct. I know I am correct because I experienced this. Before we start flinging poo at each other I want to reiterate that I do not know if it actually causes an overheating situation or if it just triggers the temperature sensor.
Re defiance of logic, because we are talking about a mechanical object with sensors and nothing is ever perfect there there will always be an opportunity for an unexpected consequence in the system, which in this case would be the triggering of a sequence of ECU commands because it receives a notice that the A/T fluid is getting dangerously hot even though the A/T fluid is not dangerously hot. The ECU is being told "warning! warning! fluid too hot!". I do not know if the fluid is actually getting too hot or if the temperature sensor is being triggered in another way and telling yelling at the ECU to shut 'er down when in fact the fluid temperature is fine. I am unequivically asserting that as long as the ECU gets this warning it will shut the engine down.
The A/T temp warning light was triggered and my engine stopped running. It started again 5-10 minutes later because it had been sitting and it cooled down. It conked out 3 minutes and 10 blocks later because the sensor triggered again so the A/T temp warning light lit up and the engine shut down to protect itself from me, the driver. My outboard engine does the same thing if the oil reservoir gets too low.
It is not particularly sophisticated technology. You add a protocol which triggers when a sensor reaches a predetermined limit. It reaches the limit, triggers a response from the engine management system, which cuts electricity to the spark plugs so they stop firing or cuts electricity to the EFI relay so the fuel injection stops working or tells whatever component or system to stop doing what it does bc there is a problem. When I pull the EFI fuse my truck won't start.
Why can't the ECU receive a tap on the shoulder when a temperature sensor exceeds a certain temperature? Why can't the ECU then cut power to the ______ (fill in name of component here)? It is a basic binary decision tree, an If-Then sequence of events, which is how a computer works (If I remember correctly). It processes the particular If-Then decisions defined by the coding (software) programmed into it. This is what a computer does, process If-Then commands.
My 1999 limited will produce a temperature reading on a ScanGauge. My Transmission temperature sensor and ECU were built in such a way that they can produce specific temperature readings, not just trigger certain events when a predetermined level is reached. I know the Earlier 3rd Gens do not produce a temperature reading on a ScanGauge. I don't know if this is because of ECU reprogramming or of it is because Toyota started installing revised temperature sending units in the 99 model year.
So the capability of my 1999 engine to do what it did exists.
I will ferret out the Googles I found about the over full reservoir and A/T temp sensor and post the links. Can't find them right now.
You're turn.
 
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OP's 2002 is 11 years old. My 1999 is 14 years old. They are not limited by 20 year old technology.
I understand what you are saying.
I am correct. I know I am correct because I experienced this. Before we start flinging poo at each other I want to reiterate that I do not know if it actually causes an overheating situation or if it just triggers the temperature sensor.
Re defiance of logic, because we are talking about a mechanical object with sensors and nothing is ever perfect there there will always be an opportunity for an unexpected consequence in the system, which in this case would be the triggering of a sequence of ECU commands because it receives a notice that the A/T fluid is getting dangerously hot even though the A/T fluid is not dangerously hot. The ECU is being told "warning! warning! fluid too hot!". I do not know if the fluid is actually getting too hot or if the temperature sensor is being triggered in another way and telling yelling at the ECU to shut 'er down when in fact the fluid temperature is fine. I am unequivically asserting that as long as the ECU gets this warning it will shut the engine down.
The A/T temp warning light was triggered and my engine stopped running. It started again 5-10 minutes later because it had been sitting and it cooled down. It conked out 3 minutes and 10 blocks later because the sensor triggered again so the A/T temp warning light lit up and the engine shut down to protect itself from me, the driver. My outboard engine does the same thing if the oil reservoir gets too low.
It is not particularly sophisticated technology. You add a protocol which triggers when a sensor reaches a predetermined limit. It reaches the limit, triggers a response from the engine management system, which cuts electricity to the spark plugs so they stop firing or cuts electricity to the EFI relay so the fuel injection stops working or tells whatever component or system to stop doing what it does bc there is a problem. When I pull the EFI fuse my truck won't start.
Why can't the ECU receive a tap on the shoulder when a temperature sensor exceeds a certain temperature? Why can't the ECU then cut power to the ______ (fill in name of component here)? It is a basic binary decision tree, an If-Then sequence of events, which is how a computer works (If I remember correctly). It processes the particular If-Then decisions defined by the coding (software) programmed into it. This is what a computer does, process If-Then commands.
My 1999 limited will produce a temperature reading on a ScanGauge. My Transmission temperature sensor and ECU were built in such a way that they can produce specific temperature readings, not just trigger certain events when a predetermined level is reached. I know the Earlier 3rd Gens do not produce a temperature reading on a ScanGauge. I don't know if this is because of ECU reprogramming or of it is because Toyota started installing revised temperature sending units in the 99 model year.
So the capability of my 1999 engine to do what it did exists.
I will ferret out the Googles I found about the over full reservoir and A/T temp sensor and post the links. Can't find them right now.
You're turn.
plane and simple your wrong... our vehicles are running on 20 year old technology first of all, thes trucks were designed and brought to life in 1996, the design process too at least three years start to finish, its 20year old tech.

you can drain all the coolant and all the ATF and run the vehicle, you can drail all the oil and run the vehicle... there is NO fail safe system on our trucks. i dont know who told you there is but they are wrong, ask any toyota tech or any person on here who as done any substantial work on their 4runner, -go ahead ask away... they will all tell you there are no fail safes on this vehicle of this nature, in fact the only on that i can think of is the neutral safety switch... i have ran my truck till the AT/temp light came on on the dash and continued the run it(while parked and at idle to let it cool down) and this took me at least 15min for the temp to drop enough to shut off the light. my truck did not shut down, it did not stall ect, it kept running. if i had shut it down it would have taken much longer than the 5-10min you are talking about to cool, as the fluid would be stagnant and sitting inside the rad its hot temps, and inside the tranny itself(where the temp sensor is) and the tranny will really hold the heat in. circulating fluid will cool much faster especially if you have a external cooler -as i do and did. but even at that it was 15min or so before the light went off. -and thats not the only time i have seen the light on and never had the truck shut down.

while yes the 99 and newer truck did receive some updates, the sensors are still the same dumb sensor. it only give the ability to send signal out to the computer which then in turn tells the operator via an idiot light that you have a problem, but it will not shut the motor down. some can give specific readings but thats it, they are not going to override the ECU .the only thing that the ECU will do that is remotely similar to this is with knock sensors, and that will adjust or play with timing signals and those are only sending out a basic signal its up to the ECU to try and figure out what the deal is, and if it cant, it reverts to a "safe" mode while still not fixing the issue. it will not shut the motor down if it seas a problem... if our ECUs are so smart then how come they can not be re-flashed and played with for say items like a TRD supercharger and larger injectors, or the 7th injector ect, why cant they adjust via the o2 sensors when lean or rich mixtures happen -too lean and you can blow the motor, crack pistons, blocks, heads ect... too rich and you can burn up cats, or o2 sensors... how about coolant temps, too hot and you can blow the motor there, but no coolant temp sensor will shut the motor down. the technology simply was never put into our vehicles. and you will never find it in our vehicles unless someone has found a way to re-wright the entire ECU and implement that tech into it -oh and im just gonna bet youd probably need new sensors that would work with the new system and for that you are talking all one-off tens of thousands of dollars into development...

as for your out board motor its a simple switch that is a on/off swtich that does that, its a dumb switch, there are no settings other than on(has enough oil) and off(not enough oil), its basically the same thing that triggers an idiot light, but its just wired in to the spark/ignition.
 
I haveto side with the kid on this one, i've seen in cash for clunker programs when 4runners are ran with freaking salt and bleach as fluids, even with the dash as christmas lights the truck still ran till its last rep.
 
did too...

(added 11/20. It may have been my Coolant Temp idiot light, but this does not change the fact that my engine did shut itself down to avoid damage).
I actually experienced this. It was not a figment of my imagination. It actually occurred. There was a direct correlation between the engine shutting down and the A/T temp warning light coming on. 3 times in a row. When I removed some coolant from the res. it started and ran as normal, no issue since.
You seem to be telling me that what happened to me didn't actually happen, or am I misunderstanding?
There is a difference in how the transmission temperature sensor works in my '99 compared to 4Rs from earlier years. A scangauge in my 99 will display actual tranny temp while 98 and earlier will not. I do not know if this is due to a sensor redesign or different ecu programming or both or something else.
I wonder if I can recreate the engine shut down scenario. Denver (altitude), late April, res. was topped off when engine was warm. Coolant level was well above full line when engine shut down.
These were the circumstances. It is late Fall now, perhaps a bit cooler. I installed a separate tranny cooler since then so I would need to detach the lines and reattach them to the radiator. Kind of a hassle but doable.
Let me keep searching for the Google I found at the time.
if our ECUs are so smart then how come they can not be re-flashed and played with
they do what they are programmed to do. Just because you and i cannot reprogram the ecu doesn't mean it cannot be manufactured by Toyota with different parameters/instructions.

i have ran my truck till the AT/temp light came on on the dash and continued the run it(while parked and at idle to let it cool down) and this took me at least 15min for the temp to drop enough to shut off the light. my truck did not shut down, it did not stall ect, it kept running.
is that truck '99 or later?
 
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you can keep searching all you want, i even encourage you to go to a dealer or any other toyota tech and ask their opinion, but they will all tell you what i am telling you, the system can not and will not do that. i will not argue with you over your motor shutting down, but it was not because the trans was too hot, or that they over filled the coolant expansion tank. they systems are not linked, there is not sensor in the coolant system other than coolant temp sensors, and they do not have any control over the running of the motor other than to signal rich A/F mixtures when cold and just fired up, and normal A/F mixtures when the motor reaches normal operation temps.

if your motor shut down on you like you say it did, and i have no reason to think you are a liar, so i will believe it did, then it shut down for some other reason not related to either the trans temp or the coolant temp or level. NEITHER of those two(or three) will affect if the motor runs or not. again our trucks do not have any fail safes like that and if anyone tells you they do, they are wrong/misinformed or other wise. -i dont even think the new toyotas do.

if your motor shuts down unexpectedly for some reason it might have thrown a code, did you check engine light come on? if so what was the code that triggered the light? if no check engine light came on, that would tell me that you experienced a problem with the ignition system.
-even BMW (i use them because i worked a dealer for a while as well as an independent shop and know there systems pretty well) will throw a code if the motor is shut down due to a safety precaution/fail-safe. it will store the code and tell you what happened(if you read the codes). -if you had no codes i can assure you that there is no way that the ECU took over and shut the motor down out of is AI thinking.
 
Boom!

you can keep searching all you want, i even encourage you to go to a dealer or any other toyota tech and ask their opinion, but they will all tell you what i am telling you, the system can not and will not do that. i will not argue with you over your motor shutting down, but it was not because the trans was too hot, or that they over filled the coolant expansion tank. they systems are not linked, there is not sensor in the coolant system other than coolant temp sensors, and they do not have any control over the running of the motor other than to signal rich A/F mixtures when cold and just fired up, and normal A/F mixtures when the motor reaches normal operation temps.

if your motor shut down on you like you say it did, and i have no reason to think you are a liar, so i will believe it did, then it shut down for some other reason not related to either the trans temp or the coolant temp or level. NEITHER of those two(or three) will affect if the motor runs or not. again our trucks do not have any fail safes like that and if anyone tells you they do, they are wrong/misinformed or other wise. -i dont even think the new toyotas do.

if your motor shuts down unexpectedly for some reason it might have thrown a code, did you check engine light come on? if so what was the code that triggered the light? if no check engine light came on, that would tell me that you experienced a problem with the ignition system.
-even BMW (i use them because i worked a dealer for a while as well as an independent shop and know there systems pretty well) will throw a code if the motor is shut down due to a safety precaution/fail-safe. it will store the code and tell you what happened(if you read the codes). -if you had no codes i can assure you that there is no way that the ECU took over and shut the motor down out of is AI thinking.

Factory wiring diagram manual
4. FAIL- SAFE SYSTEM
When a malfunction occurs in any system, if there is a possibility of engine being caused by continued control based on the
signals from that system, the fail-safe system either controls the system by using data (Standard values) recorded in the
engine control module memory or else stops the engine.
 

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well i have talked with my father inlaw(a senior tech for toyota with 25+years of dealer work under his and another 10 before that for independent shops, been sent to numerous schools by toyota, and know the vehilces backwards and forwards, talked with another tech athe local dealer, as well as the parts manager(who used to be a tech and also has over 20 years with toyota, and campaigns a toyota race car) and all of them agree that toyota has no fail safes for this motor.

supporting evidence (as t4r4life pointed out) the cash for clunkers program, how come none of those fail-safes prevented damage? rods braking and punching holes through blocks, how come no fail-safe prevented that?, the "pink milkshake" how come no fail-safes prevent those? over heating and warping heads or cracking heads/scoring cylinders, how come no fail-safes prevent that from happening all of those things cause far more serious damage than simply over heating the trans or over filling the coolant expansion tank. while ok maybe it might be "programed" into the computer system, it has never once worked... and thus it does not exist for our vehicles. i stated earlier that if it was there, then it would trip a code and be stored i the computer and it would tell you that your vehicle was shut down to prevent damage. -find me the code for this.

you can drain the trans of its fluid or over fill the fluid and run the vehicle... you can drain the coolant, or over fill the coolant and run the vehicle... you can drain your oil, or fill it with twice the amount... you you can have the timing off at any position you want it at your(it might not actually run depending on how far out you have it, but it will sure try) vehicle will not automatically shut down to save itself. but if you feel so convinced that it will feel free to try either of the above methods and report back your findings.

just because you find a document saying something exists does not mean it actually does. dodge claimed in 2011 its newer 6.7 would produce 350hp and over 800ft-lb... well a bunch of owners started disputing these clames and guys started testing it... turns dodge was not even close, 320hp average, and around 680-700lb-ft... they went after dodge and dodge finally conceded and offered all 2011 owners either to buy back the trucks or to re-flash the computers and bump them up, what they didnt do was upgrade the torque converters in the auto trucks to handle the added power, and so there was a lot of trany failures premature (cummins also supposedly has fail-safes in place to prevent catastrophic damage... funny they didnt work either). while the late model 2011 trucks got updated torque converters to handle the added power to meet dodges claims. but mileage suffered tremendously with both trucks as a result. and the DPF and emissions systems started failing, thus the class action lawsuit's filed against Chrysler. my point here is again, dont believe everything you hear or read. -i dont even think 4th gen 4runners or 2nd gen tacos have fail-safes.


speaking of fail-safes, if you have a friend or know someone with a newer say 2011 or newer BMW like a loaded 7series, here is a cool little trick to play on them... if they are driving(only do this at slow slow speeds like backing up out of a parking spot or pulling into one, and be safe about this), open your door, just a crack... it will automatically put the car into park and stop the car, the driver unless he knows about it will be like WTF!? -we would do this all the time at the dealer, some tech or lot attendant would be driving by moving a car(slow speeds again, under 5mph in the shop) and we would open the rear door as the car passed, about 2 sec later boom park and the driver would look around like WTF!? it was great fun, untill some idiot lot attendants got into it and swung open a door on a car that didnt have this feature and it hit another car and almost ripped off the door, $9000 later and one less lot attendant there was no more fun and games to be had at BMW. so be smart about this guys. dont try this on the fwy at 60mph(i honestly dont know what would happen, i have no idea cause none of us were dumb enough to try it), and dont swing the door open or let go of it, all you have to do is just open it so the open door sensor is tripped like what it would take to trigger our idiot lights.
 
all of them agree that toyota has no fail safes for this motor.
just because you find a document saying something exists does not mean it actually does.
(added 11/20. It may have been my Coolant Temp idiot light, but this does not change the fact that my engine did shut itself down to avoid damage).
My 4Runner Brother, Thats all I've got right now. My experience + Toyota Factory Manual with authentic translation errors.
Does your father in law have access to the 2002 Electric Wiring Diagram? Will he please look at Engine Control diagrams, which I think are in the System Circuits section listed in the index? Please ask him to see if there is text after the diagrams. Does that text have the heading 'SYSTEM OUTLINE' with 4 sub categories, 1. INPUT SIGNAL, 2. CONTROL SYSTEM, 3. DIAGNOSIS SYSTEM, 4. FAIL- SAFE SYSTEM (capital letters from copy/paste, not me yelling).
If he can and that is there will he please explain what 4. FAIL- SAFE SYSTEM refers to/describes/means/yadda yadda? Please ask him what "...malfunction occurs in any system…" ...fail-safe system either…" "…or else stops the engine" means. I would really appreciate it if he would be willing to do this because I would love to understand it.
If he does not have access to the manual would you please forward the screenshot I posted? I think I can send you all 9 pages of the Engine Control section if you pm me. Can I attach images and such in pm's?
recap:
First I'd like to confirm this info is in the 2002 Official Factory Electrical Wiring Diagram manual.
second: If so, what is it telling us.
Thanks
 
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Yeah PM me that info, ill pass it on to him and see what he says.


Sorry this thread has gotten so far off track. OP, have you heard anymore back about your rig?
 
My 4Runner Brother, Thats all I've got right now. My experience + Toyota Factory Manual with authentic translation errors.
Does your father in law have access to the 2002 Electric Wiring Diagram? Will he please look at Engine Control diagrams, which I think are in the System Circuits section listed in the index? Please ask him to see if there is text after the diagrams. Does that text have the heading 'SYSTEM OUTLINE' with 4 sub categories, 1. INPUT SIGNAL, 2. CONTROL SYSTEM, 3. DIAGNOSIS SYSTEM, 4. FAIL- SAFE SYSTEM (capital letters from copy/paste, not me yelling).
If he can and that is there will he please explain what 4. FAIL- SAFE SYSTEM refers to/describes/means/yadda yadda? Please ask him what "...malfunction occurs in any system…" ...fail-safe system either…" "…or else stops the engine" means. I would really appreciate it if he would be willing to do this because I would love to understand it.
If he does not have access to the manual would you please forward the screenshot I posted? I think I can send you all 9 pages of the Engine Control section if you pm me. Can I attach images and such in pm's?
recap:
First I'd like to confirm this info is in the 2002 Official Factory Electrical Wiring Diagram manual.
second: If so, what is it telling us.
Thanks

If you are so confident about the failsafes, please make a video of your truck with no oil in it and showing the motor shut off in it's failsafe mode.
 
the fail-safes that i know of are the sun roof closing half way, and then you having to press the button again to get it to close all the way. the rear window when rolled down, you can not activate the rear wiper or rear defrost. the rear locker will not engage unless you are in 4wd lo range and under 20mph, if you go faster the locker will disengage to prevent damage or a possible crash. im sure there are a few others, but none that i know of to shut the motor down, i emailed those to him and another guy i know who knows toyotas pretty well we shall see what they say.

i also PMed them [MENTION=94888]EatonKyleH[/MENTION] to get his take on this, i know he is darn good with both wiring diagrams and electrical systems across the board, plus he is a tech for toyota, so maybe his imput would help shed more light here. if i am wrong i will look silly i know, but it wont be the first time and probably wont be the last time. but i dont think im wrong(no one ever does).
 
thekid, just for the record -- kyle isn't a tech *for* toyota, but he knows a lot about the 4runner :)

he just stated in another thread he works for a family-owned mechanic shop that started in the 50s.
 
thekid, just for the record -- kyle isn't a tech *for* toyota, but he knows a lot about the 4runner :)

he just stated in another thread he works for a family-owned mechanic shop that started in the 50s.

oh... for some reason i thought he worked for toyota... ok my bad... see what i said about being wrong, i was wrong, and i feel silly... :brick::doh:
 
i also PMed them [MENTION=94888]EatonKyleH[/MENTION] to get his take on this, i know he is darn good with both wiring diagrams and electrical systems across the board, plus he is a tech for toyota, so maybe his imput would help shed more light here. if i am wrong i will look silly i know, but it wont be the first time and probably wont be the last time. but i dont think im wrong(no one ever does).

Haha I've been summoned again!

thekid, just for the record -- kyle isn't a tech *for* toyota, but he knows a lot about the 4runner :)

he just stated in another thread he works for a family-owned mechanic shop that started in the 50s.

I have worked for Toyota in the past. I've been and have currently been working for an independent shop specializing in Toyota's (and other imports) though for the last 7 years.

oh... for some reason i thought he worked for toyota... ok my bad... see what i said about being wrong, i was wrong, and i feel silly... :brick::doh:

used to.... Doing the same makes/models day in and day out bored me to death.


I'll get back to this soon. I just came out of surgery and am still a little woozy from painkillers:crutch:
 
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hey i have my combat life saver certs, and emergency wilderness first aid ect, and my wife is a OR nurse im sure we coulda done the surgery for you a lot cheaper... just sayin network bro network
 
hey i have my combat life saver certs, and emergency wilderness first aid ect, and my wife is a OR nurse im sure we coulda done the surgery for you a lot cheaper... just sayin network bro network

Haha I appreciate the offer.
It's not really a big deal since I have Health Insurance paid completely by my employer... another reason I don't work for the dealer.

anyway back on topic. Should be up for typing my essay on this jazz by tomorrow hopefully but please don't hold me to that either lol.
 

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