LB7: Reverse Lights and the BCM

[MAXX IT OUT]

Long story short my reverse light are not getting power at the under hood fuse block, if I probe the fuse with power the lights work. Does the BCM control power supply to the fuse or is there a switch on the steering column? I am asking, because every now and then I get a code that is "lost communication with BCM". If the BCM is triggering stuff, probably would explain why my Glow Plugs don't seem to work either.

 

[JoshH]

Here is the wiring diagram (assuming for the '01 in your sig).

 

[MAXX IT OUT]

Here is the wiring diagram (assuming for the '01 in your sig).

Yep Josh its the 01 and thanks for the diagram. I will see if I am getting voltage to the NSBU Switch. Is there another symptoms that can tell me that the NSBU switch is bad?

 

[MAXX IT OUT]

I found this on DP


"This info applies to 2001/2002 model years. Not sure about other years.
Here's a few of the signal generated from the NSBU. There may be more.

-Electronically tells transmission what gear is selected, (no mechanical links and levers).
-Allows START command when in Park / Neutral.
-Back-Up Lamp supply volatage.
-Back-Up Alarm
-Allows A/T Shift Lock when in RUN or START, PARK position, and brake peddle not depress
-Will automatically lock doors, (if programmed), when not in PARK
-Gear selected indication"

 

[ironmax]

I've got a thread on here about a similar issue, but I also lost my signal wire for my brake controller( wont come on when brake pedal is depressed) and third brake light only comes on when I manually operate my brake controller. Haven't had a lot of time to really dive into it lately. So hoping for some direct locations. I need to pull the under hood fuse block and see if some critters got in there. Wouldn't be the first time.

Sent from my SM-J337A using Tapatalk

 

[MAXX IT OUT]

Well just to update everyone that is interested, I ended up rolling under the truck to find that someone had replaces the NSBU plug and that a couple of wires had burnt out between the splice and the plug. You couldn't really tell by looking at wire, but give it a pull and the wire came apart. I spliced two of them back together and got reverse lights back as well as my shift lockout back.
Does anyone have the pinout for the NSBU plug, I would like to see if thats what is causing my auto door locks not to work as well.

 

[DAVe3283]

Here you go.

 

[MAXX IT OUT]

Here you go.

Thanks