battery amperage

2000 MAZDA PROTEGE

174,000 MILES • 1.6L • 4 CYL • FWD • MANUAL

ZEMORZEMOR

MEMBER
486 POSTS

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

WRENCHTECH

✓ASE Certified Mechanic
20,761 POSTS

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

ZEMORZEMOR

MEMBER
486 POSTS

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

WRENCHTECH

✓ASE Certified Mechanic
20,761 POSTS

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

ZEMORZEMOR

MEMBER
486 POSTS

i hooked up the clamp at the positive battery cable coming from the alternator.

Jul 10, 2016 at 6:14 PM

KHLOW2008

✓ASE Certified Mechanic
41,814 POSTS

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

ZEMORZEMOR

MEMBER
486 POSTS

there is no difference when i turn on headlights

Jul 23, 2016 at 6:48 PM

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