A question for the techs. I have a 12 Tacoma that hit the left front corner and I replaced an apron, upper rail and core support, sent it to paint and when I went to get it to put together, the brakes are locked up. There was a left front wheel speed sensor wire pulled apart in the accident, but it has been replaced and code cleared. I can get the pressure to release if I cycle the pressure release solinoids through the scanner, but it builds pressure again when you hit the brakes. Wondering if anybody has encountered this before?
-
Help Support Hardline Crawlers :
12 Tacoma brakes locked.
- Thread starter Fordzuki
- Start date
skinny_pedal
Well-Known Member
Do any codes come up when the brake locks up? Is it just the left front locking up? Have you tried unhooking all ABS sensors and see if brakes lock up?
I think it has to do with the electronic braking system needing recalibrated..
It did have an abs code, but it went away after I swapped wheel sensor wires and reset the code. It has (or had) a code for master cylinder pressure value not 0 or something along those lines, but it seems to have gone away when I did the yaw sensor recal. This is where I'm stuck, is there were two codes for yaw sensor after disconnecting the battery and touching pos and neg cable together for 10 seconds. I went through the entire process of trying to recalibrate the yaw sensor value twice, and I finally got rid of the c13xx code but the c1210 code is still there. During the recalibration process, the scanner says the abs and tsc off lights should blink when the process is complete, but only the abs light blinks. I haven't even seen a tsc off light illuminate at any time, but the traction control light is solid illuminated at all times. There are also codes for the right front impact sensor, and the collision line sensor in the seat (which haven't arrived yet) which makes me wonder if the abs system is tied to the airbag system, and the yaw can't be calibrated if the airbag system has a fault.
I also did a wheel sensor test and all sensors have the same values for both speed and accel while the brakes are free. Once I touch the brake pedal, the brakes lock up again, building pressure every time you hit the pedal. It's almost like a collapsed line holding pressure, but you can get it to release by triggering the release solenoids with the scanner. Each wheel has a hold solenoid and a release solenoid. :eeek: The truck was running and driving fine monday when I drove it over to paint, and had just the abs and airbag lights on, and it drove out of paint to the parking lot this morning fine.
And just fwiw, it's all wheels locking up, I posted before jacking the back up to check. And another thing to consider is there is a recall for the '12 tacomas for the electronic braking system, but it's just supposed to turn lights on the dash on, not lock up the brakes. :haha: It's supposedly fixed by a software upgrade, and I'm not sure if this truck has been flashed.
Whatever it is, it sure pissed on my day, but if we can't figure it out tomorrow, it'll be toyota's problem. :haha: I'm 99% sure it's in the software end of things. But I'll try unplugging the sensors tomorrow and see if it helps. Only other last thing I was going to try it backing the pushrod off a little and seeing if it releases pressure, but it would seem that the problem would have existed the entire time if it was a mechanical problem like a bent pedal bracket.
WHITE TRASH1
fruit stripe
I fawking LOVE my carbureted trucks. We don't own anything that even has EFI at this point.
