Proyota
New member
I'm hoping someone can help and point me in the right direction. My wife and I have a 2004 Toyota 4Runner Sport V8 AWD. We love this vehicle and it has served us well over the years.
VIN: JTEBT14R048- - - - - -
Model: UZN215L-GKAGKA
Recently we had VSC, Trac Off, ABS & Brake warning lamps illuminate. (No MIL). After scanning I wasn't able to communicate with the ABS/VSC system.
I took the 4Runner to our local Toyota Technician in town. After the vehicle was inspected I was told the skid control ecu was failing and needed to be replaced.
I replaced the skid control ecu and performed the zero point calibration using Techstream and all seemed well.
The following day I started the vehicle and as soon as I put it into gear (reverse or drive) all the warning lamps re-illuminated again.
I scanned using Techstream and fault code C1336 was present. I performed a health check with Techstream but was unable to communicate with ABS/VSC System.
I unplugged the skid control ecu (ign off), then reconnected and re-scanned. I was now able to communicate again and fault code C1336 was not present. I attempted to perform the Zero Point calibration but the skid control ecu went off line and would not communicate. I cycled the ignition off and restarted. The warning lamps off and no fault codes present. I performed a road test and the vehicle performed normally. While test driving, I monitored the abs / vsc data stream. All speed sensors and steering angle sensor seem to be functioning properly.
I'm able to perform 1 or 2 drive cycles before I get the warning lamps and loss of communication with the ABS / VSC system. I'm at a loss and the technician doesn't seem to know what to do either.
Please let me know if you have any ideas. I'm wondering if a YAW sensor could be failing and causing the skid control ecu to crash / quit communicating. But I have no fault codes for that either.
VIN: JTEBT14R048- - - - - -
Model: UZN215L-GKAGKA
Recently we had VSC, Trac Off, ABS & Brake warning lamps illuminate. (No MIL). After scanning I wasn't able to communicate with the ABS/VSC system.
I took the 4Runner to our local Toyota Technician in town. After the vehicle was inspected I was told the skid control ecu was failing and needed to be replaced.
I replaced the skid control ecu and performed the zero point calibration using Techstream and all seemed well.
The following day I started the vehicle and as soon as I put it into gear (reverse or drive) all the warning lamps re-illuminated again.
I scanned using Techstream and fault code C1336 was present. I performed a health check with Techstream but was unable to communicate with ABS/VSC System.
I unplugged the skid control ecu (ign off), then reconnected and re-scanned. I was now able to communicate again and fault code C1336 was not present. I attempted to perform the Zero Point calibration but the skid control ecu went off line and would not communicate. I cycled the ignition off and restarted. The warning lamps off and no fault codes present. I performed a road test and the vehicle performed normally. While test driving, I monitored the abs / vsc data stream. All speed sensors and steering angle sensor seem to be functioning properly.
I'm able to perform 1 or 2 drive cycles before I get the warning lamps and loss of communication with the ABS / VSC system. I'm at a loss and the technician doesn't seem to know what to do either.
Please let me know if you have any ideas. I'm wondering if a YAW sensor could be failing and causing the skid control ecu to crash / quit communicating. But I have no fault codes for that either.
Last edited:
