Ok, 91' rodeo in great shape everything worked like a champ... Pulled engine to do a rebuild on it and now my AC/heat control switch inside does not work once all back together! I went from T.B. injection to a full Edelbrock carb. system all is good engine, trans, gauges, lights, all except ac/heat controls! I cant get anything to happen, ac pump won't kick on, fan motor has no power...Oh an I cant get the control panel with switch out of dash without damaging it. Can some one lend advice please?

 

might be the wires that went to iac on the thing that idles up the moter for ac use . maybe if it dosent cense that conection it wont allow the ac to come on because the idle will be to low and cause the engine to stall. well maybe worth a try

 

Is there a way to trace down those wires by color code or witch main harness plug that was on originally? Also that doesnt account for the fan not working on heat as well..., Idk its an aggravation that I must solve!

 

the book says there is a relay under hood on passenger side for ac its location eb-5 have you cheked it? i tried looking up wire colers but it shows difrent ones

 

All I have is two relays and one fuse for the AC/heat under the hood and nothing in the fuse panel in the truck. I checked and replaced both of the relays with no change and the fuse has power going threw it but as for the switch in the dash I cant get to the back of it to run a check to see if there is power to it as well. Ive contacted every place I could think of to purchase a new switch just in case that is the problem but even the dealer says they are unavailable... If i could trace down that wire u mentioned earlier that might have every thing to do with it. I have two books on this truck and not one has a decent wiring diagram that helps me with this and I cant find one without buying the dad burn thing off the net without seeing it first... It sux!

 

i would start with a multimeter and start checking why the compressor is not coming on. Starting at the back of the compressor and going to the switch in the dash. I know there is a push button switch in the dash that you can access if you pull the ***** off the front of the HVAC unit and slide the plate off you can pull the switch forwards and check it to see if it works.