battery amperage

2000 MAZDA PROTEGE
174,000 MILES • 1.6L • 4 CYL • FWD • MANUAL
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ZEMORZEMOR
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i hooked up amp meter clamp on the positive battery cable. the clamp did not read zero amperage?

i hook up to another car at idle with headlights on and ac on it read 44 amps.
Jul 10, 2016 at 3:44 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
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WRENCHTECH
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That is right. It will only read amperage if current is being pulled from or put into the battery.
Jul 10, 2016 at 5:01 PM
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ZEMORZEMOR
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when i hooked up the clamp the car was running with the headlights on, but no amps. i am confused.
Jul 10, 2016 at 5:50 PM
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WRENCHTECH
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The headlight were taking out and the alternator was putting in. They may have balanced out. The only other explanation is you were just using the meter wrong.
Jul 10, 2016 at 5:52 PM
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ZEMORZEMOR
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i hooked up the clamp at the positive battery cable coming from the alternator.
Jul 10, 2016 at 6:14 PM
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KHLOW2008
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Try adding the electrical load or lowering it to see if there are any differences. Eg, turn on A/C or off the headlights
Jul 15, 2016 at 8:04 AM
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ZEMORZEMOR
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there is no difference when i turn on headlights
Jul 23, 2016 at 6:48 PM