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Re: Follow up on Barry's suggestion (archive)
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Posted by AC on February 03, 2002 at 14:24:27:

In Reply to: Re: Follow up on Barry's suggestion posted by eric_m3 on February 03, 2002 at 13:59:43:


Barry is correct on this.

I went to the garage and checked voltage on my battery w/ a load tester hook up and it read 12 volts.

I then started the car and let it run at idle and checked voltage again. still 12 volts.

Then I ask my wife to help me in the garage ( she gives me that I ain't pumpin' the brake pedal look ) but comes down stairs and sits in the car.

I have her start to slowly build revs and tell me when the battery and other lights go out and then hold the revs.

She yells and at the same moment the volts go to 13.8 or so and stay.

I tell her to let off the throttle and the volts stay @ 13.8.

checked the ETM but cannot find any explanation except that there is a resistor which allows charging to continue even if the battery indicator bulb burns out. HHHMMMMM.

Why does the bulb allow charging? Cannot see anything in the ETM which explains why through analysis of the schematics.

Anyone chime in w/ the answer? Apparently Avaiaion Electronics training in the USN is useless here!

Eric

You are correct there is a resistor in parallel with the lamp bulb. Since bulbs burn out periodically and in this circuit if the bulb burn out there will be on charging. In the earlier cars without the resistor if your battery bulb burn out the car would not charge so the resistor was introduce to prevent this occurrence.


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