Blinker blows everytime I start

I have been having problems with my blinker. It started that it just stayed solid when I put my blinker on. I replaced the bulb and it would work fine. Then I went for a drive and my left blinker didn't work again. I narrowed it down to it just blows the bulb in the left everytime I start the car. I just put a new one in and it worked fine, then started the car and now the bulb is out.

This is in a 1990 comanche.

Long shot but does it maybe blow the bulb when you hit the brakes? I forget how MJ tail lights work with regards to shared filaments and grounds for turn signals and brake lights.

I'm kinda surprised it blows bulbs, I would think it would take more voltage to do that, and the only ways the wiring can fail will give it less voltage.

I just put my last bulb in and it was working while on for about a minute. It blows the blinker filament(there's two filaments). The other filament seems to just be the running lights.

It is impossible to have the bulb blow unless your alternator is putting out too much voltage. The system normally has 12 volts. The bulb will run on 12 volts all day. So unless the alternator is over charging, you can never put more than 12 volts across the bulb. Now having said that, most likely is the blinker module.

Figured it out, what happened was is my original bulb would no longer blink. I went to the parts store and they told me it was an 1156 bulb, it is not. I pulled my bulb out, the glass had separated from the metal so I mangled the metal taking it out. The numbers on it were illegible. I walked up to the 1156's, looked right next to them and saw what i thought were bulbs(1154). 1154s are a 6volt bulb but are identical physically to a 1157. It took me blowing out four bulbs, checking all my wiring and diagrams until I went online to check that my bulb was rated for 6volts. I even noticed at the parts store that in little tiny letters on the front of the package it tells you what it's rated for.

That explains why they blew. Glad you figured it out.