Q: Alternator is not charging my battery while running.

asked by on December 05, 2016

When not running, there is no parasitic draw on the battery. But when I drive, the battery slowly loses power and eventually dies, leaving the truck immobile until the battery is changed or charged. The battery and/or alternator could not be it, since they have both been replaced more than 3 times. I also have replaced the computer, with no resolve. I have a AUDIOVOX VAT-1 passive started disable module, which when i start the truck, chirps 25 times, one second per chirp, in five chirp intervals. Sometimes the led light will blink, and my truck wont start until I lightly tap the key box installed under the steering wheel. My step dad supposedly checked wiring connections from the alternator to the battery, and their grounds, and they were secure. Could the drain be from the audiovox vat-1 or anything else? Thanks

My car has 217000 miles.
My car has a manual transmission.

It sounds like you may have already answered your own question. The aftermarket VAT1 alarm may be malfunctioning if you have to tap it to get the vehicle to start. This system may block the alternator from charging the battery. I would recommend having a mechanic like one from YourMechanic come and check the charging system to determine if the aftermarket alarm is interfering with the alternator charging. You may need to have alarm removed and vehicle wiring put back to original connections.

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