Need Help Fast

I have a 2002 explorer sport trac and the battery light flickers on and off and the head lights dim when the truck is on the highway doing 70 mph or higher. Once this starts, it does it all the time regardless of the speed until the truck is turned off and is restarted.

The battery test fine and the altenator was just replaced. The belt was inspected and looks fine. All fuses in the side of the dash and under the hood have been pulled and look fine.

All of this occured recently at the exact same time the drivers side door lock stopped working both power and manual, it is just stuck.

Any suggestions of what it could be?

When you say the alternator was just replaced, do you mean right around the time this all started, before, or after. If it's before or right around the same time, it could be a bum alternator or a bad/missing ground, broken wire when the alternator was reinstalled.


You say your door locks are acting up. Maybe your auto lock keeps trying to lock your doors and your power door lock solnoid is dead shorting out and causing a powerfluctuation. I know this is a long shot since it should be poping a fuse if this was the case, but who knows. Try finding your power door lock fuse, disconnect it and go for a drive to see if the problem goes away.

Since your lights are dimming, your charging light is comming on and you've had alternator work done, I'd suspect a charging system problem.

Something else. Do you have a remote start on your vehicle? Remote starts are infamous for producing weird electrical gremlins when they go for a crap.

Denis

Thanks for the response Denis.

The altenator work was done about two months before the problem started, and I don't have a remote starter.

The lock on the driver side is frozen. It won't move move manually or when I hit the button. However, I noticed last night that the light on the passenger side lock button stayed on after I turned the truck off and removed the key. This is a new problem. So I will try your suggestion and pull the fuse to the door locks and see if there is maybe a short causing the problem.

If this doesn't work I guess I am going to have to assume the computer is wrong and replace the battery, altenator and belt.

Regardless, thanks again for your imput. I never would have thought about pulling the fuse to rule out a potential problem.

....However, I noticed last night that the light on the passenger side lock button stayed on after I turned the truck off and removed the key. This is a new problem.

Are referring to the lock icon staying lit? If so, the icon is illuminated by an LED that is powered by the interior lights. If the dimmer control for the instrumentation illumination is turned up, the button should light as well. Do you have a headlight delay? If the headlights or parking lights were on when you noticed that switch lit, that is why. All the rest of the instrumentation illumination should have been on as well.

....If this doesn't work I guess I am going to have to assume the computer is wrong and replace the battery, altenator and belt.

The Powertrain Control Module (PCM) should not be much of a suspect with the issues you mention. I agree with denisb that the alternator and wiring for it should be your focus at this point. In addition, make sure the serpentine drive belt is in good condition and not slipping on the alternator when under load. Now the GEM module on the other hand could be involved, but would not cause a seized power lock.

Does the key work to unlock the door, or is that stuck as well?

-Rod

You guys are not going to believe this. But the reason for the power drain and the battery light.....the transmission fluid was a quart low. I don't know why or how, but as soon as I added a quart last night, all of the problems vanished.

You're right, I don't believe it. Are you absolutely sure it was the battery light that was on?

Keep us posted if the light comes back on.

-Rod

I second that!

sounds like a bad ground to the sensor on the tranny or to the ECM.