When I put my 89 240DL wagon into reverse (manual trans), the front passenger's side turn signal light comes on, and the right-turn signal blinker on the instrument panel becomes partially lit. Also in this condition, if I switch the turn signal on to the right, it does not blink; it operates correctly to the left. Very strange. Any ideas/thoughts would be greatly appreciated.

OK, now I hope that you'll tell us where you found a bad ground - if indeed that is what you found.

Thanks!

I'd definitely go with a bad ground, but it'll be in the taillight. That's the only place the two circuits will come together.

Inspect the black wires coming from the circuit wires on the taillight, and the screw on the body where the thing is grounded. Remove the screw, clean off corrosion with sandpaper or a small file, and reinstall. If it's a push-on connector on the taillight, remove and clean that tab as well.

The whole light comes off the car with just a couple of 10mm nuts, to make it easier to service. Be sure to protect the rubber gasket if you remove it, to prevent leaks.

Good luck!
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Rob Bareiss, New London CT ::: Roterande Fläkt Och Drivremmar!

Usually if the "wrong" thing operates, it's due to a bad ground connection on the "right" thing that should have operated. The current tries to go somewhere, and it somehow finds a path via - in your case - the passenger side turn signal. Which doesn't operate fully and correctly, but the bulb gets some current so it lights up to some degree.

In the auto tranny version, I'd check the ground wire in the shift lever housing. It's screwed to the heavy sheet metal. I don't know if or where the standard tranny version has that ground, but it's likely somewhere in or near the shift lever assembly, near where the switch/contact is for the backup light switch.