Door locks constantly locking and unlocking

[LakeGastonHank]

This problem is driving me crazy and has been for years. My door locks (all 5 of them on my 98 Suburban) lock and then unlock constantly until battery is dead or I remove the circuit breaker in fuse panel. Then, no electrical door locks or seat controls. That will drive anyone crazy, right? I've been told it is BCM, but my wiring diagrams and the dealers go, Huh? What BCM? Please, any ideas?

 

[someotherguy]

Relay might be bad? I don't know where it is on a '98 Suburban but on my '94 Suburban the door lock relay was under the dash just above the driver's side of the transmission hump. It turned out to not be the problem on mine (it was staying engaged, forcing the doors all unlocked full-time) but in my case it was the aftermarket alarm that was installed new in '94. The installers had erroneously added lock relays which would have been needed on a 2-door (no factory relay) but not needed on the Suburban where they could have just tapped the control lines and let the factory relay do the job. They put the added relays in the kick panel area and they eventually corroded.

Richard

 

[KokaineCowboy]

Do you have keyless entry?

I had a similar issues with my tahoe, took me awhile to trace the source, I thought it had something to do with my stereo wiring so I pulled most if it only to find out my wiring wasn't the culprit. I had a clicking sound from under the dash related to the locks and I also had my interior lights flickering too, drove me nuts.. My wife refused to ride in the truck at night cause the interior lights would flicker, so she walked alot.... (jokes)... But yeah, so if I may suggest, review the two links below and find this module on your truck, its a pain in the ass cause you need to lie on your back and dig way up under the dash near the steering wheel to remove it, I think its only three bolts which are a pain to reach, once you get it out and unplug it, if your locks stop cycling you know thats the problem.

If it is the problem you can simple go to any wrecking yard and pull another one and replace it and do a fob relearn and your set. also I recommend doing the range extension while in there! Works waaaaaay better... Hope this helps and good luck.

I think the module is called the remote function actuation module...

https://www.gmt400.com/threads/exte...ur-trucks-keyless-entry-via-the-module.34622/

https://www.gmt400.com/threads/remote-keyless-entry-receiver-location.44449/

 

[andy396]

I have a spare one out of a ‘99 suburban.

 

[KokaineCowboy]

I wanted to add, I'm assuming you have factory keyless entry...

Also you can use your existing key fobs that you may already have no need to get new ones you just need to do that relearn.

Also, I have more photos of the module from when I removed it, I took pics of the part numbers and the actual module, if you want them I will have to see if I can find them just let me know.