Need help tracing electrical short.

[Texas53]

I trying to help out my nephew with his '84 GMC 1/2 ton. Something is draining down the battery each night. The battery and alternator have checked out ok. I disconnected the alternator and starter and ran an ohm meter between the fuse block supply wire and ground and there is a 5 ohm load or short. I then pulled fuses one at a time and it looks like the problem is in the "Stop/Hazard" circuit. I examined the brake lights plus all four blinkers and didn't see anything wrong. I also disconnected the wires from the stop light switch. The short is still there. Any suggestions how I can trace this problem down further? Thanks for any help. Mike

 

[DrMike]

RE: Need help tracing electrical sh

Just a thought. Try checking the flasher unit. It may be your short source.

Mike

 

[Texas53]

RE: Need help tracing electrical sh

Thanks for the suggestion. I tried that but no luck. I ended up pulling the fuse block off so I could trace the wires better. The feed to the Stop/Hazard fuse had two wires running from it. I cut one and as my luck goes, the short was still there. I traced the other wire and it went to what looks like the buzzer relay. I pulled the buzzer and the short went away. Looks like I found the source. I am trying to get my hands on a good buzzer module.

Looks like it is time to get a good shop manual. I had no idea that the buzzer was on the Stop/Hazard circuit. Would have saved me some time.