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DIAGNOSE – POWER DOOR LOCKS DON’T WORK PROPERLY

By Carl O’Reilly

SYMPTOM SUMMARY
The power door locks are all inoperative or a single door lock is inoperative.

USUAL CAUSE
The power door locks utilize individual solenoids in each of the doors that activate the door lock mechanism. The switch provides power to the door lock solenoids. To lock the doors the switch provides voltage to the two terminals of the solenoid. To unlock the doors the switch reverses the polarity of the voltage applied to the solenoid. An inoperative power door lock can be caused by the switch, solenoid, wiring problem or mechanical problem within the linkage of the affected door.

DIAGNOSIS
If all of the door locks are inoperative, start your diagnosis at the fuse box. Inspect the fuse that protects the door lock circuit to ensure it is not blown. Consult the fuse box placard or your owners manual for fuse designations and ratings. Operate each door lock switch in the vehicle to determine if the doors can be locked with any of the switches. If the doors lock with any one switch the most likely problem is a defective switch on the door that is inoperative. If all of the door lock switches are functional but one door fails to operate, the most likely problem is an open circuit in the circuit between the switch and solenoid or a defective solenoid in the affected door. You should listen to the affected door while energizing the door lock. If a click is heard but the lock did not engage, a problem with the door lock mechanism or linkage is the most likely cause.

PRECAUTIONS, TIPS, and NOTES
An inspection of the rubber boot and wiring harness that connects from the door frame and the door can often reveal wiring damage. A volt meter, available at any auto parts store, can be used to check the voltage to the individual lock solenoids and switches. Refer to the meters instruction for proper usage and precautions.

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21 Responses to “Diagnose Power Door Locks Dont Work Properly”

  1. Richard says:

    My Gm car doors work fine when it is cool, but is either slow or almost don’t work when hot

  2. Robert says:

    Put the key in the lock to unlock the door and the key turn 360. Will not not unlock the door. Have to unlock from the inside once get in from the other side. Have to pull up the door lock.

    • Matt says:

      Robert, the likely cause is that the plastic clip on the back of the lock cylinder is either broken or has otherwise become detached from the linkage that allows you to manually unlock the car with a key. It is also likely that there are other problems with the cylinder as it should not rotate 360 degrees you may want to consider replacing it or having a locksmith take a look and see if they can salvage the current lock.

  3. Tory Lee says:

    Hi, I have a 2005 Nissan Sentra and the power locks aren’t working. Wen I go to push the button on driver and passenger door I hear a clicking sound but all 4 doors do not lock/unlock. What can I do to fix it… Pleas Help.

  4. Garry says:

    I have a 99 Durango and the locks on the passenger side do not unlock when pushing the unlock switch on both sides as well as the fob but will lock. Any ideas?

  5. Jim Huber says:

    Hi Carl – I’m trying to help a friend diagnose door lock problems with his 2008 Chevy Malibu. The interesting aspect of his problem is that when he first gets into the car, he can actuate (open/close) all four door locks. If he tries doing it again, only three of the door locks actuate. If he tries it yet again, only two actuate. He gets to the point where only the right rear door lock functions. It’s also the case that each time he actuates the system, there is sound in the other lock solenoids, but it gets weaker with each actuation. If he turns the car off and then on again immediately, this situation persists (i.e. only the right rear door lock works). However, if he lets the car sit long enough (I’m not sure how long is long enough), the system seems to reset and the same pattern as described above reoccurs.

    To me it sounds like whatever device (solid state relay in the body control module?) is supplying the current to actuate the solenoids is able to supply sufficient current the first time the system is actuated but then degrades with each subsequent actuation. Stated differently, I’m wondering if some device in the body control module is failing such that each actuation results in it having a reduced capacity to supply current. Have you ever heard of such a thing?

    Thanks,

    Jim

  6. kev says:

    Hi, simple problem. My power locks work but will not move to actually lock/unlock the doors. I can hear the locks working with both the remote and the door switches. The lock tabs will jerk but ultimately will not move to lock/unlock positions. This is happening on a 1999 Ford F150. What could be the likely solutuion?

    • james says:

      Hey Kev,

      more than likely the actuators are out, You-tube for a disassembly video on your truck. You can either rebuild the actuators by an extra 20 minute per unit, time investment, as the resistor goes bad, and that entails breaking open the little drive motor and wrapping resistor in foil and placing back, from the comments, ppl say this fix last for the life of the truck. You can You tube that actuator rebuild also, there’s some great stuff there which will help you way more than a black and white Haynes manual with poor grainy photos. That will save $35-40 per actuator or just you can buy new actuators online or via local parts store. I’ve had several fleet F250s with power locks and you can tell they are going out as they start to get weak. while you have your door apart, make sure you lubricate all plastic parts with silicone, all metal parts with a light grease or oil. The less resistance this whole assembly has the longer I believe it will last.

  7. Cammi says:

    I have a 2005 Dodge Grand Caravan. Whether using the key remote, or the button inside the van, the 2 sliding doors may or may not lock/unlock. There’s no real rhyme or reason as to when they work. You can hear the sound, and sometimes see a slight movement, but they do not always lock or unlock.

    If this is not something I can fix myself, do I take the vehicle to a mechanic or someone special? My vehicle was just gotten into last night (probably a crime of opportunity) and my GPS was stolen and I’m getting annoyed. Thanks!

  8. Andy says:

    I have a 2004 Pontiac Montana and my power locks work only with remote not on the switches at the door. I hope you have a solution for me. Thanks

  9. Wes says:

    I have a Pontic 2002 Montana it to only locks with the remote? Do you know what the issue is?

  10. ian says:

    My alarm goes off in my car no matter what i do. Even if the keys inn ignition and i do the least of just pressing the unlock button my security system goes off. I believe the problem is that one of my doors(rear passenger) doesn’t lock our unlock when i press the button. What do i do ? Its driving me mad.

  11. Jamie says:

    My right lock makes a horrible sound when I lock with the my button device.

  12. Sarah says:

    I have a 2014 chevy impala. My issue is with the front passenger side door.

    It will not lock/unlock if trying to use my fob. While all other doors have no problem with it. The door also does not respond to the power lock/unlock button on the inside, although all other doors again have no problem.

    It will lock if I manually lock it with my key from the outside, or manually with the lock switch on the inside.

    Best way to go about diagnosing and fixing?

    • Jim says:

      First I must ask why you wouldn’t take the car back to the dealer and make it their problem on such a new vehicle? The best way to diagnose and repair would be to first remove the right front inside door panel. Since it doesn’t respond to the key fob or the power lock switch the problem is in the lock solenoid or the wiring to the solenoid. I would guess on such a new vehicle the harness connector just came unplugged from the solenoid (or actuator). With a volt meter you should have 12 volts at 1 wire going into the solenoid and ground at the other wire. These 2 wires just reverse polarity when you attempt to reverse the direction of the locks, either lock or unlock. I you have 12 volts and a ground then the solenoid is defective.

  13. Rich says:

    Carl – Love your insight! I hope you can shed some light on this mystery…

    2004 Honda Accord (4dr)

    Symptom #1: – when locking/unlocking the car with key fob, key or inside driver door switch, the driver side door will lock/unlock. The other 3 doors remain unaffected. All three doors went out at the same moment.

    Symptom #2: – After the driver side door is unlocked, within 1 min, the door will lock. This happens if the door is open, or closed, whether the car is running or not. This is not the standard Honda safety auto-locking feature.. this is a random locking within 1 min or less. I suspect that this started to occur at the same time as Symptom #1, though I didn’t notice it until I locked myself out of the car (while running) a week later.

    Thanks in advance for the help…..

  14. wayne says:

    The driver’s side on my 2004 Mazda3 is locked and cannot be unlocked with the remote or with the key. The key will not turn to the unlock position. This door also cannot be opened from the inside by manually toggling the unlock button or by activating the electric lock switch.

    When the remote is activated, no sound is heard in the driver’s door. Both power door fuses test functional. All other doors unlock/lock as per normal from outside and inside.

  15. Shane says:

    hi i have a ford fiesta 1.3 2002 mk6 i have trouble code 1310 in the gem module i have used a scan to to manually operate the central locking and boot and individually tested each door and all seem to be working and also through my 3rd party alarm the central locking works but it will not work at all through the key interior latches and the boot relese in the dash will not work i have also tried a different module with the same fault
    and using the built in test function nothing happens on any of the door latches cheers shane

  16. Jamie says:

    i press the unlock button on my car remote and only the passenger and driver doors open. but sometimes one of the back back doors opens. in some rear occasions all the doors unlock properly.

  17. doree says:

    Hello — my passenger side door unlocks manually with no problem, locks with the switch on the driver’s side door no problem. The driver’s side door used to open manually, but now I cannot get it to open using my key. It has never unlocked by using the power switch (I have to pull it up by hand), nor does it lock by using the power switch.

    In order to lock ANY doors, I have always had to hold the driver’s side inside door handle out while pressing down on the power lock button on the driver’s side door.

    As of late, the driver’s side door not only will not unlock by using my key, but now, when I go in from the passenger side and pull up on the button, as soon as I pull on the door handle, it automatically locks the driver’s side door. So… I discovered that I have to pull out the inside driver’s side door handle while pulling up on the lock button at the same time, then throw the door wide open and hope that it stays open.

    Do I have one main problem going on here, or a few?

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