Junction block location

[Wes Harden]

Anybody know where the rear lamp junction block might be located on my 2001 Suburban 2500 2wd ? this the beasty i am looking for,


I have looked around the frame rails at the rear, nothing so far.
This truck has a tank above the spare and one mid frame driver side.

 

[Truckman4life]

AllData says front of rear bumper on crossmember. They call it the rear lamp bussing block.

 

[Wes Harden]

Ill look again today. I did see anything on that cross member

 

[Wes Harden]

As a former user of Alldata, my hopes were not high, and I was not let down.
Nothing on that cross member. Loom is on body above cross member, and no junction block there either

 

[Truckman4life]

On my '07.5 chevy at work it is on the big spare tire mount to the left side. I'm wondering if yours is above the fuel tank.
View attachment 20230503_144759_02.mp4

 

[Wes Harden]

I should lower the spare and look I guess. I am not totally sold on this truck having one. Do all gmt800 have this junction block.

 

[Truckman4life]

The AllData schematic showed it did. I'll look at my two other ones at work tomorrow.

 

[bigjimmy82]

On a friends 2004 1/2t burb it was behind the passenger side wheel well, mounted to the floor of the body if I remember right. It a was full of road grime. It’s clipped in a bracket(that’s why the one end is miter cut) and you just pry it loose with a screwdriver. We changed it because the brake lights were stuck on, ended up being an issue up at the pedal.

 

[Blue85]

I thought it was in the passenger side floor at the very back, kind of passing into the rear heat and A/C box.

There almost has to be one since the harness would be on the frame rail and the body is dropped on later.

 

[Wes Harden]

After much more Google fu, I am convinced the 2001 suburban did not get a junction block. Suburbans seem to get them in 2002. I still haven't found my short. Haven't looked much more.

The license plate frame back up camera has 6 led lights, when I reverse these lights light. Towing the boat last weekend I needed to use the mechanical surge brake lock out. Seems my trailer wiring isn't powering the reverse circuit, I had thought the camera lights were hooked to the same circuit as the trailer plug.
Move inspection of trailer wiring is next step for me.