Rear AC/ heat on 2007 m1151a1

[fastmaxx09]

I have a a possible issue. My rear AC blower works great on AC. When I switch it to heat, only the front dash blower works. I haven't had to use the heat yet, so my question is , should the rear blower work when I turn on the heat, or is it just for cooling ? I would assume it should work as it does when I use the ac , but it doesn't blow when I switch it to heat .. The front works fine, just not the rear

 

[Greg841]

Mine works the same as yours. Rear is A/C only. Only one heater core in the truck.

 

[Greg841]

Also from the -10 manual

 

[fastmaxx09]

Mine works the same as yours. Rear is A/C only. Only one heater core in the truck.

Yep , I just figured that out .. I appreciate it. I moved and deleted some wires which had me thinking I left something out.

 

[fastmaxx09]

Also from the -10 manual

That's good info. Thank u

 

[maxpower_365]

I just bought an M1152 (my first Humvee). The AC doesn't work on it and only the high speed fan works (low speed doesn't seem to do anything). Could someone direct me to the right TM to start diagnosing the issue?

 

[Greg841]

I had the same fan speed problem on my 1151, ended up being the resistor behind the instrument panel. The part number was 5578307. I've found the parts manuals and diagrams are equally useful as the training manuals, the diagrams let you see what's in every system so you can start to narrow down what may be broken.

 

[maxpower_365]

I had the same fan speed problem on my 1151, ended up being the resistor behind the instrument panel. The part number was 5578307. I've found the parts manuals and diagrams are equally useful as the training manuals, the diagrams let you see what's in every system so you can start to narrow down what may be broken.

Thanks for the info on the resistor. Looks like I can buy one through HPG for $160. Is that the best place to order one?

 

[Retiredwarhorses]

Thanks for the info on the resistor. Looks like I can buy one through HPG for $160. Is that the best place to order one?

I have them used takeouts

 

[maxpower_365]

I had the same fan speed problem on my 1151, ended up being the resistor behind the instrument panel. The part number was 5578307. I've found the parts manuals and diagrams are equally useful as the training manuals, the diagrams let you see what's in every system so you can start to narrow down what may be broken.

I finally found the TM with the diagram of where the resistor is. I know you said behind the instrument panel, but a picture is worth a 1,000 words. Thanks again!