Battery Drain

[87 Bronco]

I have an 87 Bronco II that was running fine until one morning it would not start. The battery was COMPLETELY dead so I had to jump it and give it a complete charge overnight with a battery charger. I did some preliminary checking and found a 3.5 amp drain on the battery with everything shut off. I took out all the fuses in the fusebox underneath the steering wheel and still found the same 3.5 amp drain. Any ideas on what to try next or what might be causing the drain?

 

[Bully Bob]

Try dis-connecting the starter solinoid....?

 

[Seabronc]

You obviously have a high resistance short. It is most likel;y a wire that has rubbbed thru and is touching the chassis someplace. Remove one wire at a time from the starter relay post that is connected to the battery. Once you find the wire that eliminates the drain, follow it and check every place it comes close to metal. that may be easier said than done, but that is what you may have to do.

Good luck,

>-

 

[rscherer]

I have an 87 Bronco II that was running fine until one morning it would not start. The battery was COMPLETELY dead so I had to jump it and give it a complete charge overnight with a battery charger. I did some preliminary checking and found a 3.5 amp drain on the battery with everything shut off. I took out all the fuses in the fusebox underneath the steering wheel and still found the same 3.5 amp drain. Any ideas on what to try next or what might be causing the drain?

I don't know if you got this resolved yet and your problem may be differnet than mine, but I had a similar problem with my '90 Bronco II. It would just drain over time. I put a switch on the negative battery connector, but what a hassle. Finally, my radio went out and putting in a new one wouldn't produce sound! Turns out I had the premium stereo system that has an amp back in the left hand side of the truck in the cargo area. You have to loosen the interior panel below the window and wedge it out. The amp comes out pretty easily and I bought a pigtail bypass connector (don't remember the company) by doing an iternet search. Worked great.....no more battery drain.

 

[rscherer]

I have an 87 Bronco II that was running fine until one morning it would not start. The battery was COMPLETELY dead so I had to jump it and give it a complete charge overnight with a battery charger. I did some preliminary checking and found a 3.5 amp drain on the battery with everything shut off. I took out all the fuses in the fusebox underneath the steering wheel and still found the same 3.5 amp drain. Any ideas on what to try next or what might be causing the drain?

Just remembered the name of the company with the bypass - Tune Town http://www.tune-town.com/