turn signal problem

[egreen]

My 1988 Bronco II has a problem with the turn signals and stop lights. They work fine with the key in the ON position but stop working with the engine on. When the engine starts the ABS light comes on and the signals and brake lights go out. I've changed the flasher and the multi-function switch. I'm running out of ideas. Any help is appreciated. Thanks.

 

[egreen]

One of the connectors for the multi-function switch has been replaced in the past with the wires spliced into. I can't find the connector pinout on any diagrams. If anybody has access to that information I could check that. I would like to rule that out as an error.

 

[egreen]

The connector looks like the attached image. I hope I attached it correctly.

 

[Curious Hound]

Here is a link to the diagram in the tech articles on this site. This should be very close to your original wiring. The wire colors appear a bit different than the picture you posted and maybe that is the problem. Someone may have spliced the connector to the original wiring incorrectly. If you can read an ohm meter, you should be able to check the switch and figure out which contacts are made when the switch is in different positions and use that info to verify or correct the splices. Checking for the incoming voltages is a bit trickier since the flashers will not work with the connector disconnected.

When you say that the lights work fine with the key in the "on" position, do you mean "on" in the "ACC" position? or the "RUN" position? It almost sounds like something is connected to the wrong terminal of the key switch.

 

[egreen]

I think I have it fixed. It turns out it was related to the ignition switch. Go figure. I replaced it and now I have my signals back.
For the record, the key was in the run position. The lights worked until the engine was running. It is the same key position but different result with the engine running.
Thanks for the reply Eric.

 

[Curious Hound]

cool. Glad you worked it out.