93 Trooper turn-signal electrical problem – wiring diagram needed
 

Hi. I need a Trooper electrical expert to help me with a problem.

I have a 93 automatic SOHC Trooper with cruise (relevant in a minute) and my problem is with the turn signal light switch. I had an issue with the relay at first where it was constantly buzzing when I tried to signal. I eventually replaced the relay but now, perhaps because of my needing to repeatedly apply it to get it to work during the relay’s failures, the left signal no longer blinks. The bulbs have been checked and are OK. The yellow turn signal bulbs work for right turns and four-way flasher, but when left is applied, the relay does its usual clicking, but there is no light except the left-front white bulb which comes on for signaling too but does not blink.

My mechanic had a look at it when I brought the car in for another issue and said that they traced the issue back to the switch itself, that probably the contacts inside the switch assembly have popped loose. The only fix he could recommend it to replace the entire switch assembly which entails disassembling the steering wheel and column to perform. Further, the switch assembly contains all the blinker, light hi/lo, and cruise controls and as such is a $270 dealer only part plus another 200-300 in labor, taxes, etc.

This is a massively expensive fix. I have an alternate idea. My understanding of the switch is that there are two single-pole switches that close when the left signal engages, one that triggers the relay to blink power, and one that closes the left bulb circuit. A similar situation occurs with two other switches for right turns.

If I knew which sets of wires on the harness closed the left bulb circuit and the right bulb circuit (as it occasionally fails as described above) I could attach a “suitcase” type wire tap to each of these two wires sets and close the circuit with an external switch, perhaps a momentary leaf switch mounted to the turn signal switch shaft. I know that the contacts that close the flasher relay must still work because it still clicks.

If this is able to be done, I would need a wire color diagram of the switch harness to know what wires to tap and bypass. Can anyone help?

anyone?

Get a Haynes or clymer manual for it. They show the whole
schematic