I have a 2002 Chevy Suburban. My power door locks worked when i started installing a new head unit. I just used a metra harned adapter and hooked up the wire right. after this they still worked for a while then they just stoped.
I then checked every fuse none were blown i even replaced the door lock relays. I decided to go ahead and start installing my viper alarm/remote start hoping when it came time to hook door lock/unlock wires up i would find the problem. This is what i found out.
The relays all switch over when i press the unlock/lock button un the car and on the stock remote. The door lock/unlock wire send 12v signal to the cars bcm and when locked it still arms the factory alarm. It seems to send signal to the bcm to arm the alarm but the unlock motors are not trigger or something. All i know is there anr no blown fused and relays are all fine. the bcm get signal and factory alarm arms. If anyone can help in any way it would be greatly appreciated.
Oh and sense i was doing radio work i have onstar if that effects it in anyway. Thank you.
There is a 20 amp fuse in the driver side fuse box on the end of the dash for the door locks. Also check that all the connectors in both ends of the dash are plugeged in. The door lock motors run through these plugs at each end of the dash.
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sparky
make sure that all the switches in the doors are completely connected. if one swirch gets unplugged, then the locks do not work