Battery drains overnight, parasitic draw?

Hi,

Since the drawer could be before the BCM, try disconnecting it to see if the draw goes away. If it does, then reconnect the BCM. One component at a time tied into the BCM will need to be disconnected to see when the draw stops.

Here is a link that you may find helpful:

https://www.2carpros.com/articles/car-battery-dead-overnight

Let me know what you find.

Take care,

Joe

Okay, I came back to the truck and put #7 fuse back in to see if there was a draw. Strange thing there isn't a draw now, but my power-locks aren't working. I haven't tried unplugging the BCM. Should I disconnect the battery first before I unplug connectors to BCM and remove?

Hi,

Yes, I feel that it is a good idea to disconnect the battery first. However, if there is no draw at this time, the test would be moot. Were the locks working prior? I ask because you may have already identified the draw.

Let me know.

Joe

No, the locks weren't working prior. I'm thinking maybe issue with door module. It's only the front two doors they won't lock or unlock. I have to lock and unlock them manually. The rear doors and liftgate working fine.

Hi,

It could be the DDM. I looked through the schematics and there are splices, but power all comes from the same fuse. Also, they share the same ground except for the left rear.

I attached the wiring schematics below so you can reference them. Note there are three wires at each lock actuator. The one I didn't highlight is the door ajar switch. The actuator either locks or unlocks based on polarity. If you send the power in one direction, it locks and the opposite.

Also, you may want to scan the can-bus. CAN stands for controller area network. Basically, the modules are tied together via a few wires. This type of scan will provide codes regardless of the module storing them. Here is a link showing how it's done.

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

Let me know your thoughts.

Take care,

Joe

See pics below. Note: I had to cut the schematic in half to make it readable for you. I did overlap the two so you can follow from one to the next. Also, I highlighted all wiring related to the door locks for you.

Okay, thanks Joe, will look into this tomorrow after work!

Hi,

No problem whatsoever. I hope it helps. Let me know if you have questions or if I can help.

Take care,

Joe