Electrical Issue: VSC, Brake, Multi Terrain

[greatape]

Finally figured this thing out...after the ABS pump/ecu was replaced...it was reading codes for a fault in the unit.

After replacement, the issue came back again.

Have to hand it to the awesome tech at Findlay Toyota in Flagstaff, Arizona who took the time to drive around with me for an hour until we replicated the intermittent issue.

Turns out there are 2 brake switches on the brake pedal; one just turns the brake lights on when the pedal is depressed. The other is essentially a brake pedal position sensor switch, which reads to the ABS, VSC, A-Track and Traction Control ECUs...basically every bell and whistle that's attached for traction control of any kind.

This switch is located vertically behind the brake pedal itself. Apparently, a loose pin fit, when the wiring vibrated (and gravity, I suppose) caused all sorts of intermittent ground faults; essentially causing the dash to light up like a Land Rover.

Field fix was to zip tie the lower wiring so that it was tight; not allowing the pins to fall with vibration or gravity. A new wiring harness was installed, and no more issues.

Odd placement for something that could cause so many issues. I may make a guard for it, just so it doesn't get kicked or knocked.

Hope this helps!

-H-

I need to travel up to your dealership! Yesterday, I was cleaning up the rig and noticed the rear spoiler had shifted loose apparently for some time and actually has rub into the hatchback down past the primer in the paint...

 

[Hltoppr]

I've had nothing but amazing service there. They understand the modified rigs...and do quite a bit of installations of lifts, roof racks, winches, tents and the like, so the service managers and techs aren't turned off by farkles....

Let me know if you need the service manager's name and I'll get it to you.

-H-

 

[wfo9]

Good job, keeping the thread updated... Most just ask for help and then bail when they find an answer and don't even bother to post what the fix.. was.

This could be very useful to someone in the future.

 

[Hltoppr]

Seems like there are a lot of things that can cause this type of issue on these rigs... hopefully this forum can continue to provide places for owners to look when they crop up!

-H-

 

[natkidder]

Having a similar electrical issue...

on my 2013 TE. 80,000 miles. Same lift installed for over 3 years without issue.

The other morning I had a series of dash lights come on including, BRAKE, ABS, Traction, KDSS, Air bag warning and the tach and speedo went to zero with occasional bouncing.

4WD AND 4LO lights come on intermittently as does the Multi Terrain icon.

The info screen above the nav also intermittently says "Multi Terrain Select Not Available" and the compass and range info are showing "E" and sort of flickers back and forth.

In addition the OBD II Port stopped supplying power to my scan gauge.

Truck seems to drive as normal.

This happened 1 day after going to the car wash and getting the tires balanced at America's Tire. There were no lights on for the hour drive home after the wash and tire work.

Brought the truck to my local Toyota dealership and paid the $149 diagnosis fee. Kind of assumed some sort of wheel sensor got knocked or ABS wire damaged at the tire shop but the range of lights and gauge malfunctions are beyond that according to Toyota. (and similar to what rigtec pointed out initially in this thread)

At first the dealer said they couldn't get the Techstream tool to connect via OBD but finally did and found multiple codes under ABS/Traction and did a "hard reset" which got the lights to turn off. The dealer says they checked and tested all all fuses as good and found no codes after the reset. They told me the issue was fixed but of course as soon as I drove off the lot the dash lit up again.

Kind of at a loss now and guess I'll bring it back to the dealership for more diagnosis.

Now I'm wondering if something got wet that shouldn't have--seems unlikely from a carwash but I do have a CBI front bumper which could possibly allow more water up into the front end and fender liners?

My aftermarket electronics are not extensive (Baja Design fogs, Black Oak light bar, Rigid Dualys and ARB single compressor) and with the exception of the fogs, all wired through an SPOD.

Thanks Hltppr for creating this thread, it makes me feel better (a little) that I'm not alone even if I haven't solved the issue.

I will update.

 

[Hltoppr]

Hmm...well, after a couple weeks (up through trails around Ouray and Siverton as well), mine started doing this again.

Going back in Wednesday for more diagnosis.

However...it seems as if a few of us with 5th Gens are having this issue; let's keep updated as to what we find out....

-H-

 

[Hltoppr]

FWIW, I don't think this is a "getting something wet" issue, as I drove through some huge rain, lots of puddles and the like, with no issues.

-H-

 

[natkidder]

I opted not to back to the dealer before I had a look at all my fuses myself and while none were obviously blown, a few did seem loose in that I could push them down a little further.

Interestingly, the lights have remained off for about 100 miles of driving since I did that exercise. Hope they stay off.

Fingers crossed.

 

[Hltoppr]

Yeah, I did that when this first popped up and I was in Mexico.

I'm planning on making sure the main battery cables are all tight where they ground the engine and under hood fuse box.

-H-

 

[Hltoppr]

Figured I'd post a video of the symptoms. When the brake is depressed, the gauges drop off.

https://hltoppr.smugmug.com/Cars/Four-Runner/n-ncSD54/i-SBxWcbz

-H-

 

[Gabex35]

So in an attempt to keep similar issues on the same thread I thought I would pose my question here.



Since about August I have had an intermittent issue with ABS, Multi terrain, and Traction lights coming on for no apparent reason, fast forward to after I replaced both side WSS harnesses and about a month later I got what the OP was describing although mine isn't break actuation related.



I went to the dealer to have them do a preliminary diagnostic and they said they had no code thrown. I find that hard to believe seeing that these new trucks will throw a code for every little thing.



Hopefully I can upload a video of what I encountered on a trip this last weekend but essentially it started out with the typical ABS issue lights, and soon became total loss of Tach, Speedometer, Temp guage, center stack info items, OBD2 port power and a slue of warning lights.



I went through the Fuses as best I could for being out camping and found no issues. I am at a loss and would rather not throw money at incompetent dealers.



[MENTION=109773]natkidder[/MENTION] has been pretty helpful with some of his fixes but wanted to see if anyone else had some new info to add.



thanks guys.



** I cant seem to load a video from work so here is a screen shot. I was driving about 15mph here.**

 

[Hltoppr]

Looks like the same symptoms I had. Last time the dealership had it (for about 30 days) the tech basically took the dash apart, airbags and all...and when they couldn't find anything, put it all back together.

...since then (September 2017), I've had no further issues, and have put another 5k or so on the truck.

I'm somewhat assuming there was a bad connection somewhere in the harness which caused the fault; although the one condition it has not been in again is very wet and snowy roads.

-H-

 

[Gabex35]

Looks like the same symptoms I had. Last time the dealership had it (for about 30 days) the tech basically took the dash apart, airbags and all...and when they couldn't find anything, put it all back together.

...since then (September 2017), I've had no further issues, and have put another 5k or so on the truck.

I'm somewhat assuming there was a bad connection somewhere in the harness which caused the fault; although the one condition it has not been in again is very wet and snowy roads.

-H-

Thanks [MENTION=144889]Hltoppr[/MENTION], after spending the last few hours researching some more on here there have been a few cases of this intermittent issue. Natkidder mentioned having the same issue after washing his car which is ironically when I had my dash issue also, maybe water is getting in somewhere... the truck had no issues driving into work this morning. its frustrating that this seems to happen when I am on a trip as I cant get it into 4wd

 

[rigtec]

Thanks [MENTION=144889]Hltoppr[/MENTION], after spending the last few hours researching some more on here there have been a few cases of this intermittent issue. Natkidder mentioned having the same issue after washing his car which is ironically when I had my dash issue also, maybe water is getting in somewhere... the truck had no issues driving into work this morning. its frustrating that this seems to happen when I am on a trip as I cant get it into 4wd

Hi Gabex35,

Just a few yrs ago (11/2014) I had precisely the same issue/symptoms as you've described in your detailed post e.g., lost the tach, speed-o-meter, complete loss of the instrument cluster lighting (Intermittently), security icon, steering system, ABS, VSC,... and the OBD-ll was no longer communicating; according to the dealership, who told me that it was likely due to my aftermarket electrical accessories!

I knew that they were wrong because they told me that when I was coming through the bay door, and they didn't know how to check it! So... I did what any other self respecting mechanical technician would have done: I starting researching and collecting all the data that I could to figure out what suddenly went wrong... at the time I had only about 9,700 miles on the truck so a trade-in was out of the question.

I purchased a great set of wiring diagrams and begun to study the ECU's operating protocols. Well, long story short, I learned that the cause of the problem was caused by a power (electrical) loss at the 'Main body ECU Compu network'; which (believe it or not) controls/monitors EVERYTHING electrical in the vehicle! I also found out that I had a loose Short-pin, which is just there to deactivate a few of the buss bars in the main fuse/rly box when pulled!

If I were you, first... I wouldn't worry about the trouble or lose any sleep; I did that back then and it didn't help one bit! You likely lost power to the main body ECU either at the ECU-B fuse, or you could have a poorly inserted 'Short-pin'. Put the vehicle in the on position (Not the accessory position), and test across the ECU fuses and do the same with the Short-pin and find out which one isn't feeding the Compu Network!...Stay on it and you will fine it!

Should you find that there is an internal problem with the Main body ECU, I just happen to have a brand new one; still in the box in my store room so you don't have to deal with the dealership for anything, just let me know! Hope this helps... 'Best to you',

rig

 

[Gabex35]

Hi Gabex35,

Just a few yrs ago (11/2014) I had precisely the same issue/symptoms as you've described in your detailed post e.g., lost the tach, speed-o-meter, complete loss of the instrument cluster lighting (Intermittently), security icon, steering system, ABS, VSC,... and the OBD-ll was no longer communicating; according to the dealership, who told me that it was likely due to my aftermarket electrical accessories!

I knew that they were wrong because they told me that when I was coming through the bay door, and they didn't know how to check it! So... I did what any other self respecting mechanical technician would have done: I starting researching and collecting all the data that I could to figure out what suddenly went wrong... at the time I had only about 9,700 miles on the truck so a trade-in was out of the question.

I purchased a great set of wiring diagrams and begun to study the ECU's operating protocols. Well, long story short, I learned that the cause of the problem was caused by a power (electrical) loss at the 'Main body ECU Compu network'; which (believe it or not) controls/monitors EVERYTHING electrical in the vehicle! I also found out that I had a loose Short-pin, which is just there to deactivate a few of the buss bars in the main fuse/rly box when pulled!

If I were you, first... I wouldn't worry about the trouble or lose any sleep; I did that back then and it didn't help one bit! You likely lost power to the main body ECU either at the ECU-B fuse, or you could have a poorly inserted 'Short-pin'. Put the vehicle in the on position (Not the accessory position), and test across the ECU fuses and do the same with the Short-pin and find out which one isn't feeding the Compu Network!...Stay on it and you will fine it!

Should you find that there is an internal problem with the Main body ECU, I just happen to have a brand new one; still in the box in my store room so you don't have to deal with the dealership for anything, just let me know! Hope this helps... 'Best to you',

rig

Thanks Greg,
I came across some of your input on a post late last night and was going to PM you today to pick your brain. thanks for the input, I will get looking into those items. I'm sure I will be messaging you soon with some follow-up questions.

 

[mikerevelle]

Any updates?!

I'm literally sitting at the dealer now with all of these symptoms. After washing my truck (with a slight crack in the windshield) all these problems occurred.

Dealer cant figure it out, cant even connect to read codes, etc.

 

[Hltoppr]

I don't think there has been a definitive answer for any of us who have had these issues.

My dealer replaced my ABS pump as well as the brake pedal sensor, then tore the dash apart looking for the cause; with no firm solution.

Make sure the dealer opens up a file with Toyota USA and documents the fault. Like has been said in this thread before, it seems like an ECU ground fault of some type...and it will kick out the Toyota Techstream when it's hooked up.

I'm beginning to think the fault is ultimately caused by moisture somewhere in the underhood fuse block or within the main engine wiring harness...but that's my take, based upon the symptoms.

-H-

 

[Gabex35]

Any updates?!

I'm literally sitting at the dealer now with all of these symptoms. After washing my truck (with a slight crack in the windshield) all these problems occurred.

Dealer cant figure it out, cant connect to read codes, etc.

Ive been here for 8 hours.

I'm still in the early stages of this problem so I don't have anything to contribute yet. weird that three of us have had this issue after washing our vehicles. And most of the threads Ive seen on this has been within the last year... except Rigtec.

 

[keph13]

Gabex do you have Techstream set up? I know you said the dealer didn't find a code, but I wonder if they were lazy and just checked MIL/Check Engine codes, not each subsystem. Other folks are reporting issues getting Techstream to connect, but if your problem is less severe maybe you can narrow yours down that way? If you've never used it, it's really easy - there's a bunch of ECU components, which default to "unknown connection". Then when you click one it tried to connect, and if so shows any errors. So if one component fails to connect, you can point the dealer at that module; or if they all connect hopefully one will have good info.

 

[mikerevelle]

I just left the dealer.

Dash was pulled apart. Still clueless on a fix. Said it was probably my dual battery / SPOD system. To me that doesn't make sense I since everything is fused and isolated with an automatic charge relay.

They decided to completely removing my 2nd bat, SPOD and compressor. Which they’re doing now and then they gave me a rental and sent me home.

So keep me updated and I’ll do the same