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Ghost
September 6th, 2010, 08:43
OK so I have draw on the electrical system. I kept having the battery die on me every day at the Crawl. I check for a draw by putting a volt meter on the negative battery terminal to the negative cable. I started unplugging every accessory, winch, cb, lights, etc., to no avail. Next I started pulling fuses one at a time. Draw still there. I was told it might be a grounded alt. So I disconnected it too. Still there. Today I decided to disconnect the starter wires. Still there. First question: The big 40 amp fuse in the engine bay that is marked aux fuse, is that a fuse for the fuse block in the DS floor? I would assume so. Second question: Are there any circuits that are not fused?

joe_peters
September 6th, 2010, 10:35
First, not a job for a voltmeter.

Use a 12 volt test light. You are checking for amps/miliamps of draw. Modern vehicles with PCM and radio preset memories will have a constant but minor draw, and that will present as a dull glow of the test light. If the test light is bright the draw is excessive and you need to locate its source.

You were doing the right thing, disconnecting the harness or pulling fuses one circuit at a time.

Most circuits are protected with a fusible link, circuit breaker, or fuse of some sort. One exception is the starter when the solenoid is engaged.

Ghost
September 6th, 2010, 11:03
First, not a job for a voltmeter.

Use a 12 volt test light. You are checking for amps/miliamps of draw. Modern vehicles with PCM and radio preset memories will have a constant but minor draw, and that will present as a dull glow of the test light. If the test light is bright the draw is excessive and you need to locate its source.

You were doing the right thing, disconnecting the harness or pulling fuses one circuit at a time.

Most circuits are protected with a fusible link, circuit breaker, or fuse of some sort. One exception is the starter when the solenoid is engaged.

Regardless of weather I need to test for amps or volts if it is showing volts there is a draw. Starter is disconnected. If I pull the fuse and the volts are still there then the draw is still there. I even pulled each relay.

joe_peters
September 6th, 2010, 11:36
Yes, if it is showing VOLTS there is a draw. The radio, if it has preset has memory and there is a low draw circuit that will show VOLTS, but that is normal. The PCM has memory, and there again is a low draw circuit that will show VOLTS.

Good luck.