VSC TRAC, ABS lights on and off (1 Viewer)

[WeeRipper]

Hi all, I've done a number of searched about this issue here and on other forums, my situation seemed a little different and I wanted to see if anyone else had this problem.

I recently purchased 2007 LX470 with 111k miles, had shipped to me. Did some short local drives, no issues at all. Oddly one day the battery was completely dead, I jumped it, drove it around and was bringing it to my mechanic anyway for timing belt replacement, ended up having TB and pump done as well as new rack put in. They reported no issues with the battery.

Since then, the ABS and VSC TRAC lights come on, usually after driving on the highway. The BRAKE light is not on however (which is different than most reports I've read), no CEL and when I check with the OBDII there are no codes that I can bring up. The EVAP is INC which I would think expected after the battery died.

What's interesting is that I can get the lights to turn off if I quickly brake moderately at speeds over 30mph. They will then come back on a couple minutes later. Sometimes the lights turn off on their own when I'm driving anyway.

Anyone have something similar?
I've read people replaced the gas cap (new one on the way), some reports about a bad ECU, some reports about speed sensors going bad.
Thoughts?

 

[wrav001]

I have recently diagnosed the whole ECU, VSC,TRAC,TRAC unit and ABS and Brake system on my LX470. I had it for 15years and has 168,000kms. Electronics seems to be the biggest issue with these with million miles of wires.

Step 1 : Unplug the ECU unit, VSC,TRC,TRAC control unit, ABS and Brake system control cables. Clean all sockets with contact cleaner(if needed) and plug them back. Check cables for any damage. Hope this would fix your issues. Also unplug the fuses and clean the fuse box contacts.

If above fails it could be possibly VSC,TRC,TRAC control unit and worse case ABS and Brake system control unit. Highly unlikely the ECU.

VSC,TRC,TRAC control unit is cheap (US$200). This is the most common unit to fail after me browsing through lot of forums. I had this unit failed last week and just replaced it today.

 

[WeeRipper]

I have recently diagnosed the whole ECU, VSC,TRAC,TRAC unit and ABS and Brake system on my LX470. I had it for 15years and has 168,000kms. Electronics seems to be the biggest issue with these with million miles of wires.

Step 1 : Unplug the ECU unit, VSC,TRC,TRAC control unit, ABS and Brake system control cables. Clean all sockets with contact cleaner(if needed) and plug them back. Check cables for any damage. Hope this would fix your issues. Also unplug the fuses and clean the fuse box contacts.

If above fails it could be possibly VSC,TRC,TRAC control unit and worse case ABS and Brake system control unit. Highly unlikely the ECU.

VSC,TRC,TRAC control unit is cheap (US$200). This is the most common unit to fail after me browsing through lot of forums. I had this unit failed last week and just replaced it today.

Thanks for the reply. At first I thought it might have been the speed sensors, since it was coming and going and as mentioned I could get the lights to turn off if I hit the brakes moderately hard at speeds over 20 or so. Then the lights continued to stay on no matter what I did.

I ordered a new brake light switch as I read that might be aging, then I replaced the gas cap and the lights seem to be off now. I never did install the brake light switch.

I did the tesla radio mod in the interval, some lights came on at first but now everything is good.

It seems strange that the cap fixed the light issue, if they come back on again I'll replaced the brake light switch and then after do the speed sensors. Your suggestion to clean up the connections seems like an easy trial if I get there.