Power Locks - Rear Works - Front Doesn't

[cao226]

When I press the lock/unlock button (either on the doors or on the keyless entry remotes), both the front door locks move slightly but not enough to lock/unlock the door. What’s interesting is that both of the sliding door locks work fine and the rear hatch lock works fine.

Since the car is obviously receiving the signal to lock/unlock I think the only remaining possibilities are:

1) The door lock motors in both of the front doors have died (statistically this seems unlikely)
2) Since the front locks move slightly each time I press a button, maybe there is not enough power being supplied to the motors (this seems more likely to me)
3) Is it possible that both motors have corroded in a similar way and the supplied power is not enough to fight though the corrosion?

If #2, any idea what/where I can check?
Any other ideas what might be causing the problem?

Thanks in advance for any advise.

BTW - I have a 2000 Ford Windstar.

[LeSabre97mint]

Hello

It sounds like the grounds are bad. I looked at your profile and being in TX salt isn't an issue like up here in MN in the salt belt. However, I would check the grounds by taking a long wire and hooking it up to a known good ground and then conect it to the door. Try the door locks with the wire connected. If it works the grounds are bad.

Regards

Dan

[cao226]

Dan,

Thank you for your reply. Checking the ground sounds like a great idea, but of course I have a couple of questions:

1) when you say hook a wire up to a "known good ground" do you my on the car (like the engine block) or something else...like my house...(ok as I write this the 'house' idea but I'll ask anyway :-D)…also can I use jumper cables or do I need a smaller wire?

2) When attaching the wire to the door wouldn't I need to get to bare metal? Do I actually need to scrap off paint?

3) Since both front doors are experiencing the problem, do I need to ground both of them?


Thanks again for any help.

Chris

[LeSabre97mint]

Originally Posted by cao226

Dan,

Thank you for your reply. Checking the ground sounds like a great idea, but of course I have a couple of questions:

1) when you say hook a wire up to a "known good ground" do you my on the car (like the engine block) or something else...like my house...(ok as I write this the 'house' idea but I'll ask anyway :-D)…also can I use jumper cables or do I need a smaller wire?

2) When attaching the wire to the door wouldn't I need to get to bare metal? Do I actually need to scrap off paint?

3) Since both front doors are experiencing the problem, do I need to ground both of them?


Thanks again for any help.

Chris

Chris

Lets say away from the house! The ground on the battery is good. Try to find bare metal. I think you would only need to check one door. (this would prove a bad ground) Jumber cables would work if they're long enough. 12-14 g wire should be okay for this test.

Regards

Dan

[cao226]

Originally Posted by LeSabre97mint

The ground on the battery is good. Try to find bare metal. I think you would only need to check one door. (this would prove a bad ground) Jumber cables would work if they're long enough. 12-14 g wire should be okay for this test.

The ground trick didn’t work and I think I see why. I have had a look at the wiring diagram for the power locks. The left door actuator is controlled by the Front Electronic Module (FEM) and right door actuator is controlled by the Rear Electronic Module (REM). Each electronic module has its own ground and is located in a different part of the vehicle, so its make sense that since both doors are experiencing the problem, the grounds aren’t the cause.

That said, I think I am down to two possibilities:

1)The power being supplied to the actuators is inadequate.
2)Both front actuators are bad.

#1 seems unlikely since each actuator is control by a difference electronics module (FEM and REM) in addition to the fact that other components controlled by those modules are working fine (i.e. power windows). Even still, does anyone know what the voltage to the actuators should be? I can’t seem to find this on the wiring diagrams.

#2 seems to be the most likely candidate. A new actuator is $44 so maybe I will buy one and see if it fixes the issue. Out of curiosity, can an actuator be fixed?

Thanks

Chris

[cao226]

Originally Posted by cao226

That said, I think I am down to two possibilities:

1)The power being supplied to the actuators is inadequate.
2)Both front actuators are bad.

Turns out both actuators were bad. I posted info about the fix on this thread:
http://www.automotiveforums.com/vbul...74#post4015674

Chris

[gene1956]

The actuator is bad and needs replacing. This appears to be a common problem. The part is about $55 but the dealers want about $200 to replace it. There are web sites that explain how to remove the inside panel and remove the outside door handle to access the actuator. It is held in place with 2 bolts.