Chrysler Repair: Right Turnsignal Problem


Question
Hi Roland, First of all, you were dead on right about the last problem I asked you about. I have replaced my turnsignal hi/low optical horn switch and it solved the problems I was having, so Kudos to you.

I drive a 1992 Lebaron Convertable GTC 3.0L 4spd auto. I noticed the problem I'm going to describe before I replaced the complex multifunction turnsignal switch.

The Right turnsignal flashes very fast sometimes. The outside light indicators all work including the markerlights when indicating a Right turn EXCEPT for the front Right signal light. So the Right rear flasher will work, but flash very quickly, like when you have a trailer wiring problem. This Right signal problem will present itself in any of the light settings: light off (except the Right dash indicator won't glow green), Park lights on, Headlights on low, and on high, various positions of the dash illuminosity slider switch.

With the parklights on or the lights on, I will notice that the Right turn indicator on the dash glows faintly green. It doesn't blink. Just stays on. The message centre in my car picks up this malady so at night when I have the lights on, the message centre informs me the turnsignals are on via message, then starts the chiming bell which dosen't shut off unless I stop, turn off the lights and restart the car. It starts chiming again after 50secs.

This is an intermittant problem. I noticed when it is wet or when it has rained, the problem will start after 10 or 15 minutes driving in the rain. Also, I can sometimes park the car at night and all is allright, then if it has rained at night, I'll find I have the problem with the Right signal straight away.

IF I turn on the heat in the car to "floor" and get it cooking hot, I find the problem will sometimes resolve itself!! Also, a few nice warm days and the same thing. The problem goes away.

I immediately thought that this is a short caused by water OR a contact situation as warm/hot conditions causing wires to expand or dry out might be whats going on. SO..I figured it might be inside the car. I should point out I've noticed no leaks in the car. I took the lower part of the dash plate off under the drivers knees, and took apart the turnsignal switch connection and sprayed electrical contact cleaner in there, with no success with regards to the problem.
I took off the cover on the passenger side kickplate and checked the connections and looked for water leakeage in the computer thats there. No sign of leakage. Connections seemed fine. I sprayed them with contact cleaner while I had it exposed. No change.

I looked for exposed or bare wires on the Right and Left turn signal from the indicator housing up to the point it is wrapped in tape. I changed and switched around bulbs to rule them out.

This is annoying Roland!! The secret seems to be that hot or warm conditions fix this problem (Rarely happened) BUT on the odd occasion it would go wonky even if dry, although it would resolve quickly. The fact that by putting on the heat in the car on the floor seems to be pointing at wiring and/or connections under the dash where the heat can affect the expansion of the wires...or dry them.

Thankfully, I have some wiring diagrams already that you sent me: ( 8W - 612 through to 8W - 619 and relay block 8W - 725 ). This is the numbering info on the top margin.
The bottom margin lists the pages as: ( AG-AJ 59 to 66 and relay block AG-AJ 172 ).

My Dad is laughing at me as he knows wiring is my nemisis! Any help or ideas you could again offer would be much appreciated. I am SO CLOSE to getting this car completely restored...but having owned two previous Lebarons, I should know that from an electrical standpoint, they are never done lol!
Thanks again Roland,
Regards,
Rick

Answer
Hi Rick,
Rather than a short to ground I would believe there is a high resistance or an open in the circuit that goes from the right front turn signal relay to the right front turn signal filament/bulb socket, or the right front turn signal relay itself has corroded/poor contacts inside of it. Try switching out the two right side turn signal relays, or change the left front with the right front and see if the problem moves to a different bulb or not. If not, than I would focus on the front bulb/socket proper by switching out the bulb or verifying the continuity of the wiring from the socket to the relay. The contact for the bulb's filament to the socket could also be corroded.
When bulbs flash too rapidly/weakly it is usually due to reduced current rather than to completely shorted out current. But this circuit is quite unusual so it could be anything.
But the fact that the front and rear on the right behave differently causes me to look from the relay itself forward to the bulb and its socket. Both the front and the rear relays are driven by the same output from the diode pack so it probably is not the diode pack, unless it were one of the parallel wires going from the pack to each relay were compromised, the one going to the front relay.
Thanks for the rating/nomination and kind remarks.
Roland