SHELBY GT 350 Member
Joined: Jan 2011
Location: Central Massachusetts
Service Advancetrac PROBLEM SOLVED
Thank you so much Kraig1957 for providing the clues I needed to find this issue!
I have been going nuts over an intermittent "Service Advancetrac" issue for years. Sometimes on a particular road track, my dash would light up with "SERVICE ADVANCETRAC" and all of the traction control, advancetrac, and ABS-related warning lights would come on. Also when that happens, it seemed the advancetrac system would come back on, even though I had previously turned it full off. (This causes some bad results on road track where you want to drive the car yourself without "help" from the computer.)
I posted about this in various forums and FB groups, and was told that it was a known issue with these cars on the track; and the cure was to replace the ABS module with a FR500S race module; but this would defeat the Advancetrac System completely and there would be a warning light on the dash; which would make my car fail Massachusetts' annual safety inspection -- not a good solution for me.
I have seen a few other people post about this issue, and I always relayed the information above. Somewhere along the way, Kraig1957 (and maybe one other person, I don't remember) posted that they had the issue, and it was caused by the ABS/advancetrac sensor wire hitting the exhaust, melting the wire loom and insulation, and shorting out. I looked under the car but all looked good for what I could see, without the car up on a lift.
Finally last night, I got the car up on jack stands high enough to really get under there and follow the wire -- and found the issue!
Sure enough, the wiring harness was melted; apparently from intermittent contact with the exhaust. I was thrown off by the fact that the problem only showed itself on the road track, so I thought it was somehow caused by that. Apparently, only on the track were the cornering forces high enough to make the wire hit the exhaust.
Photos attached -- way up under the car, above the area where the exhaust loops up and over the axle on the driver side, is the spot where the wire loom was melted.
| 2010 GT coupe | Daily Driver with some Steeda and GT500 take-off stuff for the occasional track day