Keyless Entry Central Security Module Malfunction

[barryparris]

I have a 2002 Explorer XLT, and my mechanic has informed me that my CSM is malfunctioning, causing the below issues.
-When parked and doors locked alarm randomly sounds
-Dome light remains on
-When setting alarm with remote, horn sounds two times rapidly
-While driving, I hear random error tones emitted every so often
-Dash Open Door Lamp is always illuminated

My mechanic has informed me that the part os not made any longer and I will need to find a used replacement. He also told me that I need to be careful, making sure I have found one which will be compatible; which is difficult being circa 2002. Needless to say, this has proved to be a daunting task.

My original unit ID is 1L2T-15604-AG (pic attached)
My local dealer has told me that I should find a unit with the ID 1L2Z-15604-ED (newer build)
I have found searching the internet another unit with the ID 1L2T-14B207-AE (internet vendor telling me this unit is compatible)

Hoping a member of this forum has experience with these units and is able to guide me in the proper direction assisting me in identifying a compatible unit.
Many thanks-

 

[TechGuru]

Nothing wrong with your CSM at all!

You have a malfunctioning door ajar switch.

 

[fordysenior]

Years ago when I was a service advisor at a Dodge/Suzuki dealership, a girl brought in a Suzuki under warranty for hearing a thud sound intermittantly. Her master mechanic had told her it's in the tranny or the rear differential. I drove it, heard the thud. It turned out to be a golf ball rolling around loose under her seat. In other words, your mechanic may be wrong.
As TechGuru suggested, check your door ajar switches -- have the codes been read? A second professional opinion might be in order. And if it is the door ajar switches, I'd advise getting them from the Ford dealer. I recently had issues with mine and aftermarket ones didn't exist or didn't work.

edit add -- and if you check with the dealer, it seems the right front door switch and the drivers door switch have the same part number -- but the drivers door switch costs $20 more..

 

[mountaineer2004]

^ Doesn't the driver's door switch have that small upraised circle catch (sorry for non tech description)
for the manual key rod, which enables the key to open/lock door?
I don't remember the passenger door having that. Strange it would be the same part number.

 

[fordysenior]

Mountaineer - both switches looked the same to me, if I remember right. But check this link.
Radio stays on when truck shut down...

 

[mountaineer2004]

Right. I'm not really into details.
I was talking about the big metal latch assembly, not the switch itself.

 

[mountaineer2004]

BTW, I had the door ajar problem, and solved it by pig tailing the wires going to the door ajar sensor.
The black connector, not the gray one! All, except the driver's door, of course. Problem solved!
I can tell by hearing/sound if there's something open. No young kids ride in car anymore, so all's ok.

One of my rear liftgate window hinges recently failed, so I put the hinge together as best I could with a nut and bolt.
I made sure it would hold forever by disconnecting its power. Permanently closed now, but that's ok.
Gotta open the main rear liftgate now, but the vehicle still gets me where I want to go!

PS -- I really did repair the P0401 code problem. Gotta pass emissions.

 

[barryparris]

Thanks everybody.
My mechanic had checked all door switches and corresponding wiring for faults and did not find any. He diagnosed the problem being the CSM. Fortunately, I was able to locate a replacement on eBay and my mechanic successfully flashed the memory from my malfunctioning unit to the replacement. All issues have been resolved and the vehicle now functions properly.

Now I am looking for someone who can possibly repair my original CSM providing a backup.
If any readers know of a shop or individual capable of performing this work I would appreciate the assistance.