Is there a fuse or something to check for this option. Have changed batteries in remote Fob, but that did not fix it. Red light on Fob is lighting, but locks due not actuate.

Any ideas?

Dan

 

do the switches work on the inside?

 

Yes, Just the remote does not work.

 

There is no fuse nor relay just for the remote keys. There is an infrared sensor overhead that passes the voltage to the same circuitry as the switches in the doors. It is a rectangular piece in the center. You can easily remove it and use a multimeter to try to diagnose it.
You can wire an aftermarket one in it's place and use aftermarket key fobs. Let us know what your multimeter reads are across which wires for more assistance.

 

What light?

 

My Fob has a very small red light in the corner, approx 3/32 of an inch in diameter that illuminates when the button are is depressed. ( when good batteries are in the unit )
The Fob has worked for over 20 years, just lately has succumbed to age I guess.
Will look further into it with mutimeter.

Thanks for the responses

 

Hi

I put the DVM across all combinations of the 6 wires with open readings. Did you want those readings with board plugged in> The readings stated were with the board removed and unplugged

 

I'd start with Ohms between the wires. Most multimeters have a setting for continuity. Your searching for shorts and opens. Try between each combination of wires, then from one end of each wire to the other end.

 

Yes as I said all were open between wires on board plug connector, have not done socket from ceiling. Not sure what I should see or not see. Find it hard to believe no circuit breaker or fuse for protection. Shouldn't that circuit board be protected?

 

I sent you something. Hopefully, it shows you how the keyless entry module uses the same circuitry as the door switches. You want to ensure that you have continuity at each of the three wires from one end to its other end. If that is the same, then the circuit board for the keyless entry system is at fault. An aftermarket replacement will be an easy task.

 

Thanks for all the help. Will proceed to try to find issue.

Thanks

 

Got the diagram. All power door locks work fine, no wiring issues found. Replaced the 4 Electrolytic caps on the remote board as they were 28 years old and maybe dried out from age. That did not help. Still inoperative. Noticed PC board says "Made in France". Are they available? PART NUMBER?

Checking Fob for correct operation before going after board. Someone says it is IR not RF, is that correct?

 

I think so, but it really won't matter. You can't replace the key fob and keyless entry board independently. I can't think of a way to verify whether the fob or circuit board is at fault. You can take a wire and connect the power lead to the lock and unlock leads at the module to test the circuit, though.

 

Success!!!!

Took fob apart and removed board. Found silver surfaces oxidized a little with blackish tint and small marks. Pencil erased that off and cleaned with alcohol. IT WORKS again!!

Thanks to all for your efforts. Anyone with a non working unit should at least try this method, along with fresh batteries CR2016 2 or 1 CR2032 should work, maybe it will work for you.

old p/n for fob 56005918 New 83504801 for a 1991, maybe more years if you need one

Dan

 

I'm glad that you have fixed it.