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.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

What others are asking

Trying to find the transmission code for a 1996 ford windstar

Your vehicle uses the AX4S Ford transmission. Inasmuch as you have the 3.8L motor, your transaxle model number is PNA-WC. The Ford service part number for that transaxle is F68Z-7000-AARM. If you are having trouble with your transmission be sure...

I have a 2015 ford fusion with 58000 miles on it and was driving on the highway and a awful loud ticking noise I drove it home

Since you were running your engine low on oil you may have damaged all the crankshaft and camshaft bearings along with piston and cylinder damage. You would need to have the vehicle inspected by a mechanic like one from YourMechanic...

Engine Burning Oil

If the engine did not have excessive oil consumption prior to the repair, the rings are not likely to presently be the cause of excessive oil consumption unless you have somehow ruined the rings "overnight". There are two principal possibilities....

Can you diagnose my car without a check engine light?

Hi there. In short, yes; it's possible to diagnose a problem with a vehicle even if the check engine light does not illuminate. A professional mechanic would start by downloading any error codes store in your 2005 Ford Explorer's computer....

Brake lights not working - 2001 Ford F-250

Hi there. It sounds like you have a bad or broken ground wire. Check around the battery for a possible broken wire. Take some time and clean all the ground wires that you can find, especially under the dash. Over...

What does the reduce engine power mean

Hi there: In general, when you experience a loss of engine power in a 2008 Ford Turbo Diesel pick-up, it's a sign of two potential problems. First and most common is that the fuel or ignition system is damaged, faulty...

What are the common things to check when the check engine light comes on?

When the Check Engine Light illuminates, it indicates that Diagnostic Trouble Codes(s) have been stored in your car's engine computer. The codes themselves have to be downloaded in order to know where to begin the diagnostic. The most important thing...

Just replaced new timing solenoid sensor my car starts but won't idle

You need to make sure you are using the correct viscosity oil since too thick of oil will effect the solenoids and cam advance system. If correct oil is being used then you will need to have then cam shafts...

Alternator problem, the wipper stops as soon as you take it to the highest,cracking sound in the morning that stop after cluching

Hello. From what you describe it would appear that the vehicle is experiencing more than one issue. The first thing I would address is the alternator, as a faulty alternator can leave the vehicle stranded if the battery dies. I...

Related articles

Top 10 PZEV Cars for Eco-Friendly Drivers
Teddy Leung / Shutterstock.com The whole idea of a PZEV (that is, a partial zero-emissions vehicle), seems paradoxical. You’d think it’d have to either be zero-emissions or not in the category at all. But as contradictory as...
A Buyer’s Guide to the 2012 Ford Fiesta
This This subcompact vehicle is available as a 4-door sedan as well as a 5-door hatchback. The prices for the vehicle are very low, even for the models that are decked out with all of the optional features. Those who...
The Top 5 Selling Cars in Connecticut in 2012
Connecticut Connecticut offers plenty of rain and its fair share of snow during the winter months, which means drivers need vehicles that can handle these conditions. Top selling vehicles in previous years have included the Toyota Camry, Corolla and the...