Repair Topics / Keyless Entry and Alarm Systems

• Why wont my ignition key turn?
• How do I replace a n electric door lock
• How to check lights and horn
• How power door locks work
• How to reprogram a key fob remote control
• Car door, hood or trunk lid won't close

MORE: Keyless entry system questions

Question : 2002 Nissan Pathfinder mileage: 31,000. I have a Pathfinder and have lost both remotes. I purchased a used remote and don't know how to program it to my vehicle and was wondering if you knew how?

Answer: Your local Nissan dealer has the necessary equipment to reprogram your remotes.  Independent garages that have updated there software can help also.

Question: 2005 Lincoln Town Car miles: 25,200. I noted Keyless Entry was omitted. Was searching to learn why my Keyless Entry works on all 3 doors & trunk but fails to work on the Driver Door. To unlock the Driver Door, I must use the physical key lock. In addition, the code for punching the entry numbers (when without a key) does not work. All worked fine until car returned from vehicle clean-up shop. Wonder what could cause this malfunction & where to begin to correct problem?

Answer:   Check the door lock actuator in the driver's door it appears that is non-operational and needs to be replaced.

Question: 2001 Ford Mustang  mileage: 50,500. My trunk is popping open by itself. I can hear it happen. It sounds like I hit the "trunk" button on my remote, but I didn't. It just started happening this morning, and has continued for hours now. I keep shutting it, but it keeps opening. After it has opened, I can still hear the "pop" noise continuing. Also, I can't open the passenger side window with the button on the passenger side. It will only open from the driver's side. Could there be a problem with a fuse?

Answer: Scan the body control module and it will identify the problem you are having. There may be a short in the control module itself. It also could be as simple as a low battery in your remote controller.

Question: 2001 Cadillac Fleetwood mileage: 132,000.  The electric door lock switches will unlock the doors but they will not lock the doors.  I looked for the door lock relay but could not locate it.  Could it be the relay or something else?

Answer: You probably have a bad door switch.  Check it out under load with a 12-volt test light.

Question: 2002 Nissan Maxima mileage: 42,000.  My Maxima has power windows, locks,  remote entry/trunk release, and alarm.  The intermittent problem is that after the car is shut off and you get out and close the door, the trunk will sometimes open, and the front windows will sometimes power down about 4" (all with no action on my part).  Sometimes when you hit the remote trunk release, the windows will power down 4" on command, but not always.  We have come out to a car on Monday am with a dead battery since the trunk had opened when we last parked the car on Friday and we did not notice (light was on all weekend).  I worry about taking this to a dealer since we cannot consistently create the problem and it sounds like an expensive one to diagnose.  Any thoughts/suggestions?

Answer:  Your car probably has a bad body control module.

Question: 2004 Volkswagen Jetta mileage: 43,000.  This model Jetta has auto locks; you turn the key and all the doors lock (and alarm activates). Mine has a problem though, the drivers door locks but all the others do not.  I can hear the whine of a small motor (left side in trunk) for about 20 seconds, as if the doors are trying to lock but will not.  I figure the locking mechanism needs to be replaced.  Is it possible to just disconnect the struggling locking mechanism and just lock the doors manually?

Answer:  Yes, you can disconnect the locking mechanism and lock the doors manually. But the car should be repaired properly. It's sounds like you need to replace the lock actuator motor.

Question: 2002 Volkswagen Jetta mileage: 62,000.  The central locking system does not work for the passenger side of the vehicle.   When I lock/unlock the doors from the driver's side, the passenger side locks do not move.  I can hear a motor turning for about 15 seconds, leading me to believe the car is trying to lock the doors.  What could the problem be?

Answer:   Remove the door panel and inspect the lock mechanism for faulty or broken parts.  Replacing the broken parts that you find should cure your problem.

Question:   2003 Dodge Caravan mileage: 75,200.  I have power door locks & want to install remote opener.  Where is control box located in van?

Answer:  The control box is located under the left side of the dash-top cover.

Question: 1998 Nissan Pathfinder mileage: 140,000.  My fuel gauge and my temperature gauge no longer work.  In addition, my driver’s side door lock often freezes.   I know this is vague but if you have any ideas please help.

Answer:  The problem with your gauges may be a shorted fuse. The problem with your door locks may be a faulty door lock actuator.

MORE: Keyless entry system questions

Repair Topics / Keyless Entry and Alarm Systems

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