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Battery light won't go away

2002 Ford Taurus Se 3.0v 6l

New alternator
New battery
The car was fine until one day i decided to drive it. Ever since then My car has never been the same. Battery light wont go off no matter what. Replaced the old alternator and replace the battery. Charging is good. All fuses are good. Ecu is good. Didnt see any burnt wires. all Grounds are tight. No broken cables from what i can see. I checked all electrical wires.

Yesturday The alternator went up to 14.44 Volts the battery was at 14.31 volts when i check the battery light it was off i was able to actually drive it. When i got home I turn car off then go to turn on again. the battery light remained on so i check the alternator it was at 13.43 Volts and the battery was at 13.35. Battery light didnt go off. I tried to recreate this but it wouldn’t work. Pressing on gas pedal when the battery light on while it hot turns the car off by dropping the rpms drastic. Whenever you first start it when cold you can press gas pedal and rev the rpm. But battery light always on in process even when reving rpms. Any Helps?? I been trying work on this car daily trying find a solution.

Any computer diagnostic codes present?

The charging voltages look ok enough to keep the battery light turned off. So the problem is more likely in the warning light circuity. On a 2002 that’s probably done by a computer of some sort located in the car, in conjunction with the alternator’s voltage regulator. The proper way to diagnose this is to make the electrical tests suggested in the service data on that interface. If you just want to try something to fix it by replacing stuff, replace the alternator, and if that doesn’t fix it, next replace the computer.

Another idea, sometimes the battery light is used as a backup for other dash warning lights. For example in case the brake warning light bulb burns out, and then there’s a brake problem, at least the battery warning light turns on, alerting the driver that something needs immediate att’n. I’m not saying that’s the problem, no experience on that car, but something worth inquiring about from a knowledgably shop. On my Corolla an alternator problem turns on both the battery and alternator warning lights.

When this happened the car was running fine till i stopped and went to try turn on again. That when the battery light was on always afterwords. Then i replaced the bad alternator but was still there so i replace the battery and was still remaining there. I tried everything i can think of and have no clue what further steps i need to take place. Any help will be greatly appreciated

Check the voltage at the S terminal on the alternator when the engine is running. Voltage should be near or equal to the charging voltage. If you find the voltage correct it is likely that there is a problem with the wiring between the alternator and the instrument panel.

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the voltage is good puts the same as the battery

how would i go about fixing this. how to know it the wires that going to instrument panel

My Taurus had alt mounted top/front of motor. Easy to reach plug. I put meter on terminals and wiggled plug and voltage went up/down. Had a poor connection on plug. I put in a shim to push plug sideways and fixed it. You say new alt has same issue as before? Maybe old alt was ok?

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Unplug the regulator connector on the alternator and see if the CHARGE light comes on when the key is on.

Put a socket on the alterantor pulley (engine off of course…) and try to rotate the alternator pulley by hand. It should be next to impossible to rotate the pulley.

Maybe the belt isn’t getting a good bite on the pulley.

Old alt the volts were going everywere & wasnt delivery enough power to battery right away were the alt could of been 13volt but the battery wpuld of got 12volts & take time to go to 13volt. After replacing they rise equally

still need help.

The alternator’s output is connected directly to the battery by a thick wire. If you had 1 volt difference between the two, that means the battery was taking a lot of current to charge the battery, indicating the likelihood of a faulty battery. If you connected your new alternator to that battery, that amount of output current could have damaged the new alternator.