VSC TRAC/VSC OFF Lights stay on

[GLP]

I have an 04 Limited 4WD V8 and both VSC lights go on and stay on when I put it in drive and start moving. I have driven about 50 miles since it started and they still stay on when cold in the morning or warmed up. Prior to this I had been driving normally on dry roads. The center differential lock and DAC were never turned on. I haven't checked for codes yet but the check engine light is not on. This happened about a year ago and the lights went off after driving for about 30 minutes then shutting the engine off, they never went back on till now.

One thing to mention, this started immediately after getting the smog cert done. Here in California on 2004 they don't smog test it anymore they just do some OBDII test with some analyzer so it didn't get driven on rollers. The guy said the OBDII test would have had nothing to do with the VSC system.

Any advice?

 

[AZ4runner08]

I had an issue like this when I first bought my 08, and it turned out to be the gas cap...

 

[Range]

Yep. Check the seal on the gas cap. Just buy a new one anyway off of Amazon (they're cheap). Replace cap and disconnect the negative to your battery. Then reconnect and restart. Worked for me.

 

[BlackWorksInc]

It is not a Gas Cap, there is no OBDII DTC set in the system otherwise the MIL would have been turned on as well as the VAC/TRAC lamps.

Have you had to jump start your '04 or have you let the battery run down a bit recently? Typically what causes just the VSC/TRAC lamps to illuminate is a VSC/TRAC specific DTC that does not affect OBDII functionality. The '03 & '04 4Runner's Skid Control ECU is sensitive to voltage changes, particularly voltages around 12.2~12.0v-ish or lower. This often results in the ZPC (Zero Point Calibration) becoming reset/curropt; all you need to do then is perform a ZPC Relearn procedure (if you search the forum you'll find plenty of threads on how to do this.)

IF the ZPC Relearn does not correct the issue it is related to a ABS failure, so you'll need to pull DTCs from the Skid Control ECU with an ABS Compatible scantool.

I recommend you all read this thread to better understand the operation of the system and how to go about diagnosing it.
http://www.toyota-4runner.org/4th-gen-t4rs/151487-check-engine-trac-vsc-read-me.html

 

[cpark_12]

Mine is on now. I know the reason is that when I got my front windows tinted, the guys were playing with my headlights and light bars and killed my battery (morons!). We jumped it off and sure enough the VSC OFF and TRAC lights came on when I put it in drive. Luckily, We have a SolusPro scanner, so it'll be a fairly simple process to do the Zero Point Calibration.

 

[GLP]

BlackWorksInc was right, it needed a Zero Point Calibration. Now it's fine. Also, thanks for pointing me to your post on how the system works. That was good reading.

Have not jump started it since I got a new battery about 4 months ago. I think this was all caused by the OBDII system check that was done for the smog cert.

One thing to note, I tried the ZPC procedure 3 times with no change. Then I disconnected and reconnected the battery and repeated the same ZPC procedure and it worked, the lights don't come on anymore. Never got any DTC codes, although my OBDII analyzer isn't capable of ABS codes so I don't know about that.

Thanks!

 

[BlackWorksInc]

BlackWorksInc was right, it needed a Zero Point Calibration. Now it's fine. Also, thanks for pointing me to your post on how the system works. That was good reading.

One thing to note, I tried the ZPC procedure 3 times without success. Then I disconnected and reconnected the battery and repeated the same ZPC procedure and it worked, the lights don't come on anymore. Never got any DTC codes, although my OBDII analyzer isn't capable of ABS codes so I don't know about that.

Typically what happens is that a second ABS related DTC may also trip as a result of the VSC system not being properly calibrated. When this happens you can't perform a ZPC Relearn until you clear all the DTCs in the Skid Control ECU (ABS module) memory.

Glad you enjoyed the reading, I try to do my best to write a ton of information down for members for this type of situation.

 

[beliy25]

i have similar situation but my vsc abs trac light up when i am driving and go away after i put the car on neutral,shut it off,start again.!!! havent done any checks on codes .

 

[str8freccia]

VSC TRAC/vsc off lights

This happened to my 2004 Sport a few years back and it turned out the battery was weak, even though there were no other symptoms.. Just happened again, so I'm planning on replacing the battery again because it has been 4-5 years and 50-60K since it 1st happened. I'll report back.

 

[Darklordcreeper]

Trac

Same happened to me. Got a smog test and Trac lights came on immediately after. My 04 v8 has a bunch of issues that need to be addressed and no money to do it. Fml