I'm in the process of retrofitting the A/C system in my truck and I ran into an issue with wiring differences...

This truck originally came with A/C but it was installed at the dealer, it didn't ship from Japan with it. It has the same A/C switch in the panel, but pretty much everything else is different, the condenser/evap/lines/drier .. everything. At this point I have 90% of the OEM parts in there, but I just realized that the wiring is different.

If anyone has experience with this sort of thing I could use a pointer on where to start with the process of rewiring the truck for the OEM electronics. There are wires for AC in the factory harness but the plug for the evaporator is different.

The OEM wiring has a pressure switch built in to the evaporator and the "dealer option" which I had before didn't. It's got some kind of cheap alternative (temp probe or something) with a relay wired into it.

I've got an OEM evaporator so I'm covered on parts, wondering if anyone has an idea where to start with the process of wiring this up... The plugs are different of course.

The OEM evaporator also has some kind of control box on it, not sure what it does.

Here are a couple of pics of the two evaporators and their plugs..


OEM (Maker Option)



Aftermarket (Dealer Option)




Any advice appreciated!

 

Have you looked at The Good Book?
http://personal.utulsa.edu/~nathan-b...ditioning.html

 

Locate a copy of the Electrical wiring diagram for your truck .

wire the AC to that schematic and you should be good to go.

 

As I understand it, they all had AC added at the dealer. I could be wrong. I have added several AC to the 84-88 trucks but not the 89-95. I imagine they are similar. I would get the wiring from a boneyard and think that would just plug up correctly.

Your bottom picture above is an aftermarket kit and they are a different wiring. The aftermarket one I swapped out on an 86, I removed the aftermarket wiring and installed the Toyota wiring.

 

Thanks scope. Nope I had been looking for that

When you did this did you have the dash out and replace all the wiring in the factory harness?

I think it might be easier for me to just rewire the plug. I can chop the plug off the aftermarket one and put it on the OEM evaporator. One option at least


Does anyone know what the other box on the OEM evaporator is? The one with the control knob on plug housing on it..

 

"A/C Amplifier" -- the brains of the operation.

Discussed in the manual.

 

Just take the glove box out and you should have access to what you need. The wiring is some short sections that just unplug from each other.

 

Thanks Terry and Scope.

Looks like plug 3 is always the same



So like you say, I should just need a setup that plugs into the amplifier and pressure switch, and then to plug 3 on the other end