matoose
New member
My "06 SR5 just had the 4LO come on at 75mph tonight. Based on your experience, I'm inclined to replace the transfer case now and save the 4wd computer cost. Would you do the same, or wait?
4LO Indicator on. Not in 4WD!!
- Thread starter NCSCOTT
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chayos00
New member
If it's just the 4LO light. I'd try resetting the computer system by leaving the battery disconnected overnight. Plus exercise your 4WD system by switching from 2wd to 4HI to 4LO to make sure it all works.
By the way, I still have not seen my 4LO light come on randomly anymore after I had been to the dealer when it was newer.
lehiguy
New member
This has happened to me twice in the last year. I don't pay attention to idiot lights too much, they are so often a result of a malfunction of the nanny system. FTR, I think the T-case engagement is retarded. Manual engagement is fool proof. This system obviously has shortcomings.
matoose
New member
I did go out after my post and checked 2wd to 4HI to 4LO and the Center Diff Lock. Everything works fine and I'm fairly relieved.
I didn't think of it, but I did pull my battery out last week to change the driver low beam. It has been idling rough since then as well. Coincidence or related?
I'll disconnect the battery and check the actuator plug next and make sure it's clean and dry and add some dielectric grease and wait to see if it happens again.
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CookieRoe
Senior Member
These threads make me nervous. I haven't engaged 4Lo since I bought it. I'm afraid it will get stuck in 4Lo. That would suck. 4Hi does take some time to engages sometimes, but it engages. I try to use it as often as I can.
Would be cool to see if someone figures it out and do a DIY, but as [MENTION=66389]BlackWorksInc[/MENTION] implies, fat chance of that happening.
Would be cool to see if someone figures it out and do a DIY, but as [MENTION=66389]BlackWorksInc[/MENTION] implies, fat chance of that happening.
BlackWorksInc
New member
Honestly if I get one at work I'd do a thread on it, but we've only had one or two all year last year and I didn't get either.
NasaE30
New member
Disconnecting the battery doesn't really do anything. Sometimes it will make it worse.(matoose) Sounds to me that you have an minor issue that your ecm learned to ignore. By disconnecting the battery it now sees the fault and is running poorly. My BMW used to do this. It would take a while to sort itself out.
If you have a bad sensor, an 02 sensor for example, puling power might clear the light for a few hrs or even days. But If the sensor/part/component is broken the light will come back on. Thats what it is designed to do.
Those that are having troubles with their 4wd, I would start by switching it into hi/lo and back a bunch of times. Try to get it to work itself out. Whacking the actuator with a hammer isnt going to work, changing fluid isnt going to do anything. These are not very complicated devices. There is no black magic going on in there. It either works or it does not. Best thing you can do for any car is use it.
Athletes work out to stay strong to not injure themselves when its time to compete, same thing goes with your truck. Just once a week or month or whatever, shift in and out of 4wd, lock the center diff, drive around a parking lot if you have to, just make sure it all works and keeps working. If you are worried that it wont go or get stuck in 4lo then it sounds like you really don't even need 4wd.
If you have a bad sensor, an 02 sensor for example, puling power might clear the light for a few hrs or even days. But If the sensor/part/component is broken the light will come back on. Thats what it is designed to do.
Those that are having troubles with their 4wd, I would start by switching it into hi/lo and back a bunch of times. Try to get it to work itself out. Whacking the actuator with a hammer isnt going to work, changing fluid isnt going to do anything. These are not very complicated devices. There is no black magic going on in there. It either works or it does not. Best thing you can do for any car is use it.
Athletes work out to stay strong to not injure themselves when its time to compete, same thing goes with your truck. Just once a week or month or whatever, shift in and out of 4wd, lock the center diff, drive around a parking lot if you have to, just make sure it all works and keeps working. If you are worried that it wont go or get stuck in 4lo then it sounds like you really don't even need 4wd.
There must be a sequence in which the 4WD system engages which I'm not entirely sure of what that it as of yet. I'm going to assume that since there are more than 3 wires going to the front differential actuator that the 4WD ECM sends incoming power to this actuator first once the user switches from 2HI to 4HI. Once this actuator engages the yoke, the internal plastic gears have a set of contacts inside that rotate to complete an outgoing circuit to the 4WD ECM. From this point forward, I'll assume the 4WD ECM send a signal to the transfer case actuator to engage 4HI, thus finishing the sequence.
From this point forward, when user switches from 4HI to 4LO, I'm going to assume that this sequence is not possible unless 2HI to 4HI sequence is first completed.
From this point forward, when user switches from 4HI to 4LO, I'm going to assume that this sequence is not possible unless 2HI to 4HI sequence is first completed.
The indicator has been coming on for the last 90K, sometimes in 2HI sometimes in AWD. It goes away when drive mode is switched or the vehicle is turned off. I've never had any functional or performance problems. The dealer has not been able to figure it out. I will continue to ignore it.
CowboyAdventurer69
New member
Reload this Page 4LO Indicator on. Not in 4WD!!
I had this happen 9 times in 3 months and every time I go to the dealer no one can get a code up on the computer so to them it doesn't exist, what happened to real mechanics like in the old days who could figure this out without plugging it in. Last it's always happened over 80mph and I've driven it on a closed road course so as not to get a serious ticket or suspended license. So why can't Toyota get this fixed, LOL because they need to fix it and don't want to waste any money so if it doesn't show a code it's not a problem!
I had this happen 9 times in 3 months and every time I go to the dealer no one can get a code up on the computer so to them it doesn't exist, what happened to real mechanics like in the old days who could figure this out without plugging it in. Last it's always happened over 80mph and I've driven it on a closed road course so as not to get a serious ticket or suspended license. So why can't Toyota get this fixed, LOL because they need to fix it and don't want to waste any money so if it doesn't show a code it's not a problem!
chayos00
New member
They wanted me to bring it to them in the error state, but couldn't work on it the days it would happen so I told them I will show them in the error state and made them promise to look at it at another time. Basically they ohm checked the harness and the reprogrammed the 4x4 ecu and it never came back for me. I had even showed them pictures of it showing 4lo when I was going 60 mph to prove it wasn't in 4lo.
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therealmattryun
New member
Hi, new to the forum and new to Toyota. I bought my 2006 Limited v6 4wd at 86k this year and its sitting around 95k today. I commute around 70 miles a day, and haven't had a single issue until today, when the 4LO came on twice during my morning commute. The first time I was doing 80, passing a big rig, and I pulled over and cycled 4wd between 2wd, 4HI and 4LO. Everything engaged properly, and the light turned off when I cycled back to 2wd. The second time I was doing around 60, passing a big rig again but this time on an incline. This time I pulled over and shut the truck off and turned it back on, and when it started back up the light was off. Both times the truck acted just fine while the light was on, with no indication that anything was wrong other than the solid 4LO on the dash. I know this is an old thread, but there doesn't seem to be a ton of other people having this issue!
JerseyBiker
New member
I know this is an old thread but I want to see if anyone was able to find the cause. I have a 2013 4Runner. Today while driving about 45MPH and in 2wd, the 4LO light started blinking. I pulled on the shoulder to check if the selector was turned to 4wd and it wasn't. So I engage 4HI and it still flashed 4LO, I put it in neutral and engaged 4LO. It still flashed 4LO but also started beeping. I put it back in 2wd, the beeping stopped but 4LO was still flashing. I turned off the engine. When I started it back up everything was back to normal. This is so odd. I'm concerned that this is an indication of something going bad and serious problem may happen down the road.
I have had instance of seeing the 4LO indicator.
I recently changed struts in the 4runner, and took it out and went into 4wd normally. By that, I mean it was from a slow forward roll in drive. So, no problems.
Several months later, snow is forecast and I took the runner out, put it in 4wd, and suddenly, I am getting the steering jerk and grinding. I stop and try to go in reverse and mess with the steering and it finally comes out of that 'state'. I was happy to get back into 2wd and out of the flashing dash indicator trying to get 4wd.
I have learned now that if I put the runner in 4Wd, and I roll backwards (sloped driveway), and engage reverse, I get 4wd in and out no problem.
I do not think I have ever put it in 4wLO since buying it. But I recently had seen the indicator when getting in after using 4wd. I put the runner in 2wd and the indicator (4wLO) went out.
Very strange. I have over 160K on it and it is really reliable. I will put it in 4wd once a month now and wonder if I should do a complete change of all fluids.
Edit: by the way, no codes. I am very familiar with the VSC issue and have written about it here. If someone wants to search my posts, and can't solve it, I can run them through the solution. It really should be a class-action lawsuit, IMO.
I recently changed struts in the 4runner, and took it out and went into 4wd normally. By that, I mean it was from a slow forward roll in drive. So, no problems.
Several months later, snow is forecast and I took the runner out, put it in 4wd, and suddenly, I am getting the steering jerk and grinding. I stop and try to go in reverse and mess with the steering and it finally comes out of that 'state'. I was happy to get back into 2wd and out of the flashing dash indicator trying to get 4wd.
I have learned now that if I put the runner in 4Wd, and I roll backwards (sloped driveway), and engage reverse, I get 4wd in and out no problem.
I do not think I have ever put it in 4wLO since buying it. But I recently had seen the indicator when getting in after using 4wd. I put the runner in 2wd and the indicator (4wLO) went out.
Very strange. I have over 160K on it and it is really reliable. I will put it in 4wd once a month now and wonder if I should do a complete change of all fluids.
Edit: by the way, no codes. I am very familiar with the VSC issue and have written about it here. If someone wants to search my posts, and can't solve it, I can run them through the solution. It really should be a class-action lawsuit, IMO.
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JerseyBiker
New member
Thanks for replying. You have over 3 times the mileage I have. Today I went to meet up with a couple of friends at a bar. When I first started my 4Runner, everything was working correctly. No flashing lights. After about 10 miles I stopped at a convenience store. After I started it back up, the 4LO light was flashing again. Only this time the check engine and the TRAC OFF lights were also on. It stayed that way the 3 miles to my destination. When I left to return home, the 4LO light was now off but the check engine and TRAC OFF lights were still on, and they stayed that way until I got home. I checked the gas cap to make sure it was tight so it's not that. It seems to be running OK. I don't know what is going on here. I'll be calling the dealership first day in the morning.
My advice is to get the codes first before going to dealer (its under warranty?). Don't clear them out, just note down the codes and then see what they say. It will put you in the position of calling BS on some crap they try and pull. They might just disconnect your battery for a few minutes and then send you on your way.
I don't think if a gas cap blows a code, that just fixing the gas cap will clear the code. Same as the O2 sensor issue. And the important skid controls are off till you clear out the code.
I don't think if a gas cap blows a code, that just fixing the gas cap will clear the code. Same as the O2 sensor issue. And the important skid controls are off till you clear out the code.
JerseyBiker
New member
I used a ODBll code reader and it found the following error:
P0705 $07E8
Transmission Range
Sensor A Circuit
(PRNDL Input)
I found the following online:
"This is a generic powertrain code, which means it covers all makes/models, 1996-newer. However, specific troubleshooting steps will vary depending on the vehicle. The P0705 diagnostic trouble code (DTC) refers to a switch either external or internal on the transmission whose function is to signal the Powertrain Control Module (PCM) or the Transmission Control Module (TCM) as to the gear shift position -- P, R,N and D positions (park, reverse, neutral, and drive). The backup lights may also function through the Transmission Range Sensor (TRS) if it is an external component."
I disconnected the battery for half an hour and drove about 5 miles and the lights didn't come back on again, but I'm still going to contact the dealer tomorrow.
P0705 $07E8
Transmission Range
Sensor A Circuit
(PRNDL Input)
I found the following online:
"This is a generic powertrain code, which means it covers all makes/models, 1996-newer. However, specific troubleshooting steps will vary depending on the vehicle. The P0705 diagnostic trouble code (DTC) refers to a switch either external or internal on the transmission whose function is to signal the Powertrain Control Module (PCM) or the Transmission Control Module (TCM) as to the gear shift position -- P, R,N and D positions (park, reverse, neutral, and drive). The backup lights may also function through the Transmission Range Sensor (TRS) if it is an external component."
I disconnected the battery for half an hour and drove about 5 miles and the lights didn't come back on again, but I'm still going to contact the dealer tomorrow.
JerseyBiker
New member
oops missed this reply before I just posted. I actually did what you suggested as far as getting the code and disconnecting the battery. I didn't clear the code. I purchased the truck at a small used car chain called Auto Lenders that sell only late model certified used vehicles, 4 years ago. I purchased an extended warranty from them that is supposed to cover everything. But I only have 46K on it so maybe it's still under warranty with Toyota. I'll find out tomorrow. Thank you again.
JerseyBiker
New member
Thanks again, but I said I didn't clear the codes. I almost forgot I had that thing. I used it once about 7 years ago for an issue I had with a Tundra. It's a cheap one from Harbor Freight but it did the job. I have an appointment tomorrow morning with the dealership. I'll post how it works out.
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