Installing AC - 2002 2.3

[button_pusher]

Hello! I am currently in a wiring battle with my truck to get AC installed in a non-factory AC truck.

As of right now (using the Factory Service Manual), I need to have two basic wired systems for the AC to function.

I need an ACCS, which is basically the PCM eventually hearing, "turn the AC on," and an ACCR, which is the actual relay-based power delivery to the compressor.

Here's the ACCS system, pretty straightforward:

Just goes from the selector knob (which I have changed to the appropriate AC version), to the high pressure sensor, to the low pressure sensor, to the PCM. My huge issue here is that the harnesses either differ from year or option - I cannot tell which pin into the PCM to send this signal. If someone has a 2002 2.3 with AC, I would be eternally grateful if they could tell me which Pin and color their low pressure AC switch ends up at. (I already have another wire going into my pin 15, so that adds another layer of complexity).

My second issues lies with the second system, the ACCR.

Not too bad, just a relay I will have to slap in and add power to. My main issue here is that once again, the wire colors differ. I need to verify the Pin number and wire color exiting the PCM harness that goes to the relay.

Without trying to bug ya'll, I did scroll through about ten years of posts and found @pjtoledo and @85_Ranger4x4 had posted about this topic before and seemed very knowledgable. If you have any input I would be very grateful. Thanks in advance!

 

[85_Ranger4x4]

Without trying to bug ya'll, I did scroll through about ten years of posts and found @pjtoledo and @85_Ranger4x4 had posted about this topic before and seemed very knowledgable. If you have any input I would be very grateful. Thanks in advance!

Sorry to disappoint... my truck is so much different than yours it isn't funny. My A/C doesn't care what the ECM is doing and the ECM doesn't even know the A/C is there. Until a couple months ago my truck didn't even have an ECM...

 

[button_pusher]

Well it sounds better off than where I'm at, this PCM wiring is an absolute nightmare. I think I have a few more tries in me before I just bypass it and put it on a switch.

 

[pjtoledo]

it's confusing, my post wasn't very accurate.
more to come later.

 

[lowspeedpursuit]

Google would seem to agree for '02. OP is '07 wiring.

PCM being involved in A/C is only strictly necessary to bump your idle and activate the WOT cutoff.

 

[pjtoledo]

this is on a 2002? right?
my best info is 2005, close enough for confusion.
PCM pin 41, AC demand. from the dash switch
PCM pin 69, AC relay control, this is power going into the PCM. it really isn't much power, only powers the AC relay coil.

if the PCM is satisfied with WOT, cold engine lock-out, and the dash switch then that power leaves PCM on pin 86.
PCM pin 86, "AC clutch relay, switched output" circuit 347. this goes thru both low & high pressure switches.

that current flow energizes the AC relay.

C1008 on the battery junction box, where the AC relay plugs in. pin 2 goes to PCM pin 69.
the actual power that runs the AC coil doesn't go thru the PCM. battery junction box yes, PCM no.

2.3 vs 3.0 and 4.0 have different locations for C1008 on the BJB.

 

[pjtoledo]

oops, another attempt.

 

[pjtoledo]

C139 is near/under the master cylinder. both pins 3 & 6 go to the AC clutch coil.

 

[pjtoledo]

to thoroughly confuse you, this is a 2000. very similar to the 2005.

anything else we can help you with today?