Sorry, this is a long one. About three weeks ago the TCS on my 99 just randomly started turning itself off and on with the release of the parking brake. Then along with the emergency brake it also started doing it with the headlight switch. Then a little while later, and along with the parking brake, and the headlight switch, it started doing the same thing with the right turn signal. So now, if I release the parking brake, turn the headlight switch on, or off, or use the right turn signal, the TCS will turn off or on. It now will sometimes turn itself off and on while driving. There have been times when I get in and start the car up, the TCS will work and function fine with the button for about five minutes and then it will randomly turn itself off or on again. I have a code B2597 TCS mode switch circuit short to ground. I'm trying to figure out the correlation between the three components because it seems they share a circuit. I have checked all the grounds, cleaned and checked the resistance with a multimeter and all is good. I have checked the fuses for the ABS and all is good with those. I assume my EBTCM is working properly because I'll give it a hard brake test, and the ABS kicks in as it should. Anyone else have, or had this issue or similar? Any suggestions on where to look for short to ground that could be causing this?

 

If you have a Tech 2 or similar aftermarket scan tool you can use the flow chart below…if you are checking grounds using your ohm meter that’s not the best way…you need to check grounds “dynamically” using voltage drop…static testing tells you nothing…do you know how to check for a short to ground ??