2009 Chevy Cobalt LT 2.2L 4 DR, 176,000 mi. Sometimes the sticks come up or down..... All 4 lock actuators have the same symptoms. When i press the door lock or unlock button 7 times in a row, you can hear they are getting weaker and weaker until nothing............ wait a while and its like they "charged up", and at every press get weaker. So what i am trying to find out is do I have a bad ground, failing BCM. This has been going on for over a year but has gotten worse so since it was nice outside I thought it would be a good time to check it out. Does anyone have a pin-out for the BCM so I can check the voltage for the lock actuators and see if it drops every time I press the button? I cannot see all 4 going bad at the same time..... I tried to look up power lock schematic to no avail, cannot even find a diagram with the drivers power lock switch and the passengers lock switch.

What was done so far- Battery replaced 2 months ago, NEW drivers and passengers power lock switches, cleaned the positive connectors at the under hood fuse box.

 

Personally I'd sell it. Cobalt's were never all that great. The early ones had issues with the ignition lock, which Chevy will change for free.

 

This is normal behavior for the thermal breaker.

Does it lock/unlock when you press once?

 

the actuators all would go bad on the pick ups of that generation so why not a cobalt. We have a site sponsor that makes and sells better quality lock actuators.

how stiff are the actuators/lock linkage when the lock **** is moved by hand?
I would test for power at the actuators not out of the bcm….then you rule out voltage drop across the wiring.
the cobalt overall, maybe not the greatest but the 2.2 ecotec engine is one of the best built 4 cylinder engines ever made imo.

 

The door lock sticks move normally when pulled up or pushed down. I will have to take off all the door panels and check the power at the connectors when I get time. Other than that this vehicle has been a good one. Anyone who borrowed it cannot believe the power of a 4cyl, they call it Zippy! and it is.

 

Some times it does and sometimes it doesn't. Some move this week then not next week, very random..........