battery idiot light
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battery idiot light
Having problems with my battery idiot light. I took both batteries out of the truck and had them tested. Both show good charge. Cleaned all battey posts and terminals. The truck is starting fine now but the idiot light keeps coming on while I'm driving. I don't know if this has anything to do with it, but the air conditioner doesn't seem to blow cold air now.
Please forward some ideas to me.
KB
Please forward some ideas to me.
KB
Postmaster
Joined: Jun 2008
Posts: 2,564
Likes: 11
From: Wayyy NoCal, USA
The idiot light is supposed to indicate system is discharging. IE, the system is consuming more current than the charging system is putting back in.
Stick a voltmeter across the battery terminals when engine is running.
If anything less than 13.5 volts, you definitely have a charging problem.
Stick a voltmeter across the battery terminals when engine is running.
If anything less than 13.5 volts, you definitely have a charging problem.
Postmaster
Joined: Apr 2006
Posts: 3,524
Likes: 2
From: CA Bay Area
The idiot light in my truck is hooked up to the alternator and has no other connection to the batteries.
Meaning it monitors alternator and alternator only. Most likely you have failing board or brushes on your alternator.
Meaning it monitors alternator and alternator only. Most likely you have failing board or brushes on your alternator.
Postmaster
Joined: Apr 2006
Posts: 3,524
Likes: 2
From: CA Bay Area
If you have luck similar to mine, the alternator will pass the bench test with flying colors.
I had strange symptoms when charging light was coming on at high rpm, but would go off when I up-shifted to lower rpm. Took about 10,000 miles for the alternator to definitely give up.
I had strange symptoms when charging light was coming on at high rpm, but would go off when I up-shifted to lower rpm. Took about 10,000 miles for the alternator to definitely give up.
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