Sorry, but I've never had one apart to look at. If it's been acting up the same way for a long time without failing completely, I'd be a little more inclined to look at the bulbs. How about switching them from side to side and see if the problem follows the bulb.
Do you have a trailer harness? These vans use separate bulbs for turn signals and brake lights. Their operation has to be combined in an adapter harness to operate the single trailer light. The adapter harnesses is inserted between the two halves of the vehicle's connector somewhere near the left rear corner and can be unplugged and removed as a test. The harness I looked at once had relays in it that could develop intermittent contacts.
Another potential problem is the signal switch. It has a lot of separate contacts.
If you are near a large city in Indiana, Alabama, or Georgia, there is a junkyard chain that has very clean, organized yards where you pull your own parts, and they're very inexpensive. You might be able to find a used signal switch and tail light to install as a test.
I'm trying to find a diagram because I think the signal circuitry goes through the body computer too because the electronic signal flasher is in there. Oh, that reminds me; look up behind the brake pedal to see if you can find the flasher plugged into the assembly. It is so heavy that in some cars it droops down and breaks the contacts. These units have two relays, one for each side, but it has four output terminals, one for each corner of the vehicle.
Caradiodoc
Wednesday, March 25th, 2009 AT 1:29 PM