I don't think it's the TCS, since if that comes on it would also light up the "Low Traction" lights. However TCS coming on could be a sign that it is failing. You can disable TCS with the TCS switch down on the console. Normally the light on the switch is ON all the time, as it is active.
If the turn signal lights are coming on, when you press the brake, then I suspect there may be a wiring problem under the dash. I found on my 97 Transport, that under the carpet on the left side close to the drivers kick panel, wiring that got frayed by your foot resting in that area. Examine that area carefully, and fix/splice back any suspected wires.
Mine ended up was no rear left speaker and blew up the radio, which I had to replace. And also I found problems with my FOG lights, in which I found a problem in the Fuse/Relay center under the hood, on the left, that I ended up having to jumper a wire, to the relay that ran the FOG lamps.
I am still to this day discovering more wiring problems.
My power sliding door, and my passenger window, still plauge me. I changed the driver side switch cause the knobs break easily. I suspect the new switch is flaky, sometimes it won't go up, sometimes it is fine. Other things: The power door had a missing contact in the safety switch that is part of the back latch. I mean that it literally fell out of the switch.
Also the contact block had corrosion and had to be replaced, and the door latch unit plastic broke. Hasd to replace that, got one from Ebay was cheapest source.
Now the door worked fine for a few months, and now I need to have the clutch adjusted, as it now likes not to close all the time, and/or will not close all the way. They sure have a series of electrical problems with the entire line of them.
However I hear about this with almost all Minivans regardless of make or model.
Monday, September 17th, 2007 AT 12:02 AM