Hey guys, first time poster here. Got some problems with my Cavalier's turn signals.

Background: So last year after I bought the car, I replaced the front side markers, front turn signals, dome light, and center high-mount with LEDs (also did the rear turn signal/brake lamps, but the low resistance disables the ABS), and installed an LED flasher. I also replaced the multifunction switch with one from 1A Auto, as it was busted.

Problems: Since then, turning the switch to parking or headlamps causes the right turn arrow on the instrument panel to illuminate faintly. From what I've been reading, that probably means that voltage is leaking to that bulb from the ground side.

Also, I don't think the front side markers and turn signals are flashing properly (I think they're supposed to flash alternately when you hit the left or right turn switch). Here are the flash patterns:

With the headlight switch off - Left side marker and turn signal flash together (not alternately). Right side marker does not flash, right turn signal does.
With the switch in park - Left side marker does not flash, left turn signal does. Right side marker and turn signal flash alternately (I think this is the right behavior, please verify).
With the switch in headlights - Same as in park.

Two things I've noticed: When turning, the instrument panel flashing and the clicking are sometimes fast, and sometimes when I go over a bump, it slows back down to normal. Makes me think there's a loose ground somewhere. Also, I've been burning through multifunction switches lately after starting the car (no turn signals, no brake lights, ABS disabled). Don't know if that's just the crappy 1A Auto parts (twice), or if there's a surge or something related to these electrical problems. Ordered an OEM (brand) one off Amazon.

Full disclosure: I have almost no skills with automotive - or any - electronics, so please bear with me. I do have a multimeter and access to wiring diagrams from Alldata. I'm having a hard time reading/interpreting the wiring diagrams, and if anybody has some pointers, or links to tutorials for automotive diagrams, I'd appreciate it.

Any help would be appreciated. My plan is to sell the car soon. I bet somebody would buy it with these minor problems, but I want to take this opportunity to learn to troubleshoot car electrical problems.

Thanks!

I've had issues with LED bulbs on my Cav too.. and I'm an electrician by trade.

If you're planning on selling the car, why not just put some regular bulbs back in and not worry about it? Probably have less issues with things burning out (multi function switch) or not working (ABS).

John, thanks for your reply and sorry about the supremely late reply back (too busy at work and it slipped my mind). That's what I decided to do; regular bulbs fixed the issue, so I take it the LEDs don't work with the circuitry. All good now, going to sell it very soon.