95 gmc topkick short how to find?

Anonymous-0 · Jul 24, 2008

Went to start my truck and the battery was dead. After chargeing there is a constant drain on the battery. I have unhooked the alternator and all the fuses and there still is a 1.5 volt draw at the battery post. I would think most other things like selonid would draw much more. Any guess where to look next? The brake switch is new and no lights are on.

Brian Jasper co. Ia · Jul 24, 2008

A volt meter is not the proper way to check for a parasitic drain. You need to use an ammeter and a cable adapter so you can place the meter in the battery circuit with out interrupting current flow. When modules have a current interruption they "wake up" and you will think you have a drain when actually you don't. Your 95 probably has limited electronic content. Try unplugging the radio from the radio itself and see if your draw goes away. 15 to 20 milliamps is normal draw when all modules are inactive.

Anonymous-0 · Jul 24, 2008

The radio made no differance. I had to work on the backhoe most of the day so didn't do much on the truck. My ameter showed nothing i guess its broken.

Brian Jasper co. Ia · Jul 25, 2008

You're just going to have to go circuit to circuit with a test light in series with the battery cable. Not everything has a fuse in the I/P fuse block or the PDC under the hood. Look for simple things like a glove box light staying on. Disconnect components. Once I found a fuel pump relay stuck keeping the pump on. Another one was a stuck button on a power seat. The draw came and went as the circuit breaker opened and closed. One system at a time is how we do it at work. A test light will do it. A digital ammeter is needed to measure down to that 15 to 20 milliamps. The old analog meters aren't going to be much help here.

95 gmc topkick short how to find?

Anonymous-0

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Brian Jasper co. Ia

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Anonymous-0

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Brian Jasper co. Ia

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