2004 power locks & horn failure

[Amacneilnb]

Both the power locks (using key fob) and horn stopped working at the same time. I have checked the horn fuse under the hood behind air cleaner and it is ok. The horn will not work at all, and to lock the doors, I have to use the "lock" switch on drivers door. When I press the key fob, the locks do not change, nor does the horn sound. Is there a fuse for the fob control which could cause this?
Due for annual safety inspection and this could be the end of my much loved PT.

[JoeX]

Originally Posted by Amacneilnb

Both the power locks (using key fob) and horn stopped working at the same time. I have checked the horn fuse under the hood behind air cleaner and it is ok. The horn will not work at all, and to lock the doors, I have to use the "lock" switch on drivers door. When I press the key fob, the locks do not change, nor does the horn sound. Is there a fuse for the fob control which could cause this?
Due for annual safety inspection and this could be the end of my much loved PT.

Maybe battery in FOB????

[CREWZIN]

Since you have a first generation PT, there are a number of fuses including the door locks in the fuse box by your left knee the interior of the cabin. There's a 20A fuse that's labeled "RKE DR LKS" which is the number #3 fuse. The labels are printed on the inside of the fuse box cover.

[Amacneilnb]

Power lock issue solved. Purchased the car new in 2004 and have never replaced the key fob battery. Go figure, after 13 years it died. New battery and locks work fine now, but not a peep from the horn. Also, just replaced the original car battery 1 1/2 years ago. 300,000 km and original exhaust still intact. What a great car this has been. Any ideas on the silent horn?

[ptcruisersteve]

Do you have a voltmeter to check and see if you have voltage at the horn?

[Amacneilnb]

With my volt meter set on 20, I get readings of 6 when horn button is pushed.

[rob302]

Are you sure it was 6 and not .6 ? I only ask as the decimal can be tricky to notice when you don't expect to see it.

[ptcruisersteve]

If yours is a factory system,it sounds like the horn feature might have been disabled,which sounds every time you lock & arm(or unlock & disarm) a vehicle equipped with the sentry system.
The horn chirp that signals that the doors have been locked/unlocked can be activated or deactivated by using the following procedure:

1. Insert the key into the ignition switch and turn the switch to the ON position.

2. Press and hold the Unlock button on the transmitter for between four and ten seconds.

3. Continue to hold the Unlock button and press the Lock button.

4. Release both buttons. A chime will sound to signify that the process is complete.

[rckstein]

Originally Posted by ptcruisersteve

If yours is a factory system,it sounds like the horn feature might have been disabled,which sounds every time you lock & arm(or unlock & disarm) a vehicle equipped with the sentry system.
The horn chirp that signals that the doors have been locked/unlocked can be activated or deactivated by using the following procedure:

1. Insert the key into the ignition switch and turn the switch to the ON position.

2. Press and hold the Unlock button on the transmitter for between four and ten seconds.

3. Continue to hold the Unlock button and press the Lock button.

4. Release both buttons. A chime will sound to signify that the process is complete.

This might be a possibility otherwise, but in the OP's first post, it says the horn doesn't work at all, so I presume that means the steering wheel pad, also.

[ptcruisersteve]

Originally Posted by rckstein

This might be a possibility otherwise, but in the OP's first post, it says the horn doesn't work at all, so I presume that means the steering wheel pad, also.

Op's first statement says "Both the power locks (using key fob) and horn stopped working at the same time". So depending on if the voltage to the horn is 6 volts or .6 volts that might change where to look for the root problem.

The remote Keyless Entry Module bypasses the clockspring when it triggers the horn to work. The fact that the power locks and the horn went out at the same time tells me they both might be a related issue pointing to the programming issue. There is a possibility that the horn relay might be the issue as it can effect both keyless entry module and the horn switch. Double check fuse #14 that powers the horn relay. Verify that the horn itself works by manually apply power feed to it.