Does anyone have a wiring diagram for the AC system.
thanks
thanks
CK5
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1990 AC wiring Diagram
- Thread starter Justin Fleming
- Start date
texlurch
Old fart on a hill
tons here... looks like the light and dark greens are connected..
http://www.truckforum.org/forums/chevy-truck-forum/36278-electrical-diagrams-chevy-only-2.html
http://www.truckforum.org/forums/chevy-truck-forum/36278-electrical-diagrams-chevy-only-2.html
Kain
3/4 ton status
post 18
texlurch
Old fart on a hill
I was looking at the '89 diagram.. pretty sure they are the same.
Top right is the relay...
Other diagrams on that page show the firewall connector with pin outs, so if you can trace the cut wires back you should be able to narrow it down.....
Top right is the relay...
Other diagrams on that page show the firewall connector with pin outs, so if you can trace the cut wires back you should be able to narrow it down.....
So I am confusing my self a little, when I check continuity from the lt green on the pressure cyling switch to one of my mystery wires I get continuity as long as the ac clutch connector is connected...I am not seeing how that is happening based on the schematic as the light green wire goes to the relay and I would have expected this condition on the dark green wire at the cycling switch
texlurch
Old fart on a hill
The clutch connector is ground for the system, so disconnecting you'll get an open
On that schematic the lt grn connects to the dk green prior to the relay, between the pressure switch and relay
Let me go back and re-read your original post...
**edit*** at this point I would unwrap the harness and trace both ends of the cut green wire. On the schematics I linked there are a couple for the bulkhead connector pinouts.
Does your AC work? You mentioned cruise control in the first post.. have you traced the wires to it yet?
AC does not work at this point as I have not charged the system, I am planning on replacing all the seals and pulling vaccum on it shortly. But I could Jumper the pressure switch and see if the ac clutch comes in. If I do that for a short time that should not harm anything. If I am reading this schematic correct, if I jumper the pressure switch the AC cluth should engage as long as I am call for the AC on the selector panel and key is on right?
Yes. Just jumper it for a few seconds. If the clutch engages, then your A/C wiring is complete, assuming it's like the mid 80's trucks or like the diagram posted above. (I don't know why they have a clutch relay but still run full coil current through the pressure switch - it appears they are only interested in saving the dash switch.)
(BTW, it's confusing having 2 threads about the same thing)
The "continuity" is probably a few Ohms, not 0, since by your test, it is clearly the A/C clutch coil.
Did you ever state whether or not an engine swap had been done in this vehicle?
(BTW, it's confusing having 2 threads about the same thing)
The "continuity" is probably a few Ohms, not 0, since by your test, it is clearly the A/C clutch coil.
Did you ever state whether or not an engine swap had been done in this vehicle?
I thought that it was confusing so I put it back where my long thread of trouble shooting was at. I couldnt figure out how to delete from here.
Not sure on the motor swap or not. I just got this basket case and trying to work through the details. If I had to guess the motor has been out. Not sure if its orginal, rebuild or what. Just based on missing brackets and bolts for bell housing support brakcets etc. I have my assumptions..
