Trying to figure out what's going on with my dmax swap truck. All of the electronics are from a 2005.The keyless entry remote works to lock the truck, but generally doesn't work to unlock it. When I first got the truck running, everything was fine. It worked great for lock and unlock for a month or two, then all of a sudden the unlock function stopped working, but the lock function continued to work. I changed batteries in the remote, and did the relearn procedure but no luck. Every once in awhile, the unlock will work, but usually not. Any ideas?

 

check the solder connections in the remote itself. My 09 cobalt had the same thing happening.

 

The dealer, and most parts stores too, have a transmitter tester. You can use it to see if your fob isn't transmitting. If the fob isn't transmitting, take it apart and clean the contacts. If it is transmitting, your lock actuators are probably going bad. The actuators do have a high failure rate.

 

The internal lock and unlock buttons work fine every time...sounds like maybe the remote is bad. Next time I'm down in Denver I'll stop by a dealer and have them test it.

 

I am betting it is the button pad contact on the remote. I had fits with my wife's remote on her Cobalt. I did all the temp and home brew fixes such as gluing a piece of tin foil on the button, all eventually failing. I ended up buying new button pads for both of her remotes and they have worked perfectly for quite a while.

 

also there are relays inside the drivers door fuse panel i had a problem where my rear doors wouldn't lock with the remote. changed the relay and that solved the problem. its another idea.

 

I ended up buying new remotes, they are working fine. It was a problem with the old remote I was using.