[sevlor]

Yes I know, "Another door lock issue post"

Back story: Bought a 2006 Colorado Crew cab with ZQ8 package back in March, it was sold to me with a branded title as rebuilt. It was in some sort of accident but no air bag deployment. Best I can tell is it has had the grill, headlights, marker lights, driver side fender, and drivers door replaced at some point. When the previous owner replaced the driver door they didn't transfer the lock from the old door, so I have two keys for this truck like its they 80s again. I noticed the day I bought it that the door locks wouldn't work, either by the fob or the door buttons, all windows work with no problems. I found posts about unplugging the driver door switches and plugging them back in, and they locks will work for an indeterminate amount of time, I've had them working for a few days, and I have had them stop working mid drive to somewhere. With the key out of the ignition, pressing the door lock button on the door, I get three chimes, pressing it on the fob will not do anything but will engage the security system so when I open the unlocked door it will start honking. Over the few months I have owned it though I have had issues with the battery dying anywhere from overnight, to upwards of 24 to 48 hours after being parked, so I thought there was a parasitic drain. a couple weeks ago I decided to just put a new battery in it, and while at batteries plus they went ahead and tested the battery that came out and it tested at under 200cca, and they calculated the date code that was etched in the top and found it to be a battery from 2008, despite having a sticker on it saying 01/22, but it had grease pen marks on it like it came from a salavage yard, and all the branding stickers were peeled off. I had hoped the battery may have been the culprit but it was not, I have even taken the driver door switch block out and shorted the capasitors on it to drain them and plug it back in, and they locks worked for the auto lock out of park, but then stopped before I had even reached my destination 30 minutes later.

Does anyone have any other ideas as to how to fix this, could it be some wierd passlock issue as I have both the original ignition key and the door key both on the same key ring, I am at a loss here.

I will also add I have installed an aftermarket headunit in the truck but all these issues were also happening with the factory radio installed as well.

 

[cart7881]

A lot of baggage to unpack here. Truck was in an accident. Door locks did not work when truck purchased. You have managed to get them to work intermittently by working on the switch. The key fob appears to operate as it activates the security system.

Assuming that by referring to locks (plural), you mean all four door locks are operating, or not operating, at the same time. Also assuming that you have verified that the same condition is produced by the front passenger door lock switch.

Each time that you manipulated the switch it caused the locks to operate for a period of time. Assuming that all ot your actions were at the switch, it appears to most likely be a problem with the logic board inside the switch. Before loading the parts cannon you might want to check power and ground to the switch. Ther should be 12volts, at all times, to the Orange wire in the smaller (8 pin) connector. You can check for ground continuity at the black wire in the same connector.

Now, the above message is given assuming the wiring in the doors and eng compartment is not damaged. If the left front fender and the left front door were damaged and replaced, the wiring involved could have been affected.

 

[sevlor]

Yeah, if I unplug the driver door switch unit for 30 seconds and plug it back in, the locks will start working again for all four doors, but as stated in my post they my work for several days or they may stop working in 30 minutes, The issues I have been seeing all seem similar to the standard door lock issues that there are dozens of posts about on these forums except I never lose power window control. I can go through and try out voltage testing, as well as ground testing.

I did decide last night to remove the bettery, and zip tie the possitive and negative cables together over night, I haven't gone back down and hooked everything back up yet, but we'll see if maybe that helps.

Does anyone know with a "normal" operating truck if the action taken by it's BCM if the keys are still in the ignition and the door lock is pressed is to not lock the doors and to ding three times, or is that chime just an indication of an issue?

 

[cart7881]

If I leave the key in the ignition and the doors are closed, the doors just lock. If the key is in the ignition and the door(s) open the chime will ring constantly until the battery dies, regardless of lock button press or not. That's normal key in ignition warning. If I try to lock the doors during that time the doors will lock and immediately unlock.

With door open and the key out of the ignition, when the lock button is pressed the chime rings 5 times and the door locks move to the lock position.

 

[sevlor]

If I leave the key in the ignition and the doors are closed, the doors just lock. If the key is in the ignition and the door(s) open the chime will ring constantly until the battery dies, regardless of lock button press or not. That's normal key in ignition warning. If I try to lock the doors during that time the doors will lock and immediately unlock.

With door open and the key out of the ignition, when the lock button is pressed the chime rings 5 times and the door locks move to the lock position.

Ok so afater almost 24 hours with the battery out and the battery cables zip tied together, the locks worked last night from the fob to lock the truck, worked this afternoon to go grab lunch, i tested them a couple times on my drive, locked the truck with the fob at the restaurant, they also worked when leaving, but got back home and they no longer worked again. With the door open and key out of the ignition, it does chime 5 times, but doesn't lock.

Something I forgot to include in the first post, the driver door lock solonoid does seem to be on the week side, could that possibly cause issues like this?

 

[cart7881]

I don't think a defective driver's door lock would cause the other three doors to not lock.

 

[Unfettered]

Possible bad wire between the door and truck body?