Who is an expert in fixing the AC? Anyone have the wiring manual EWD090F? I've pulled out what remains of my hair trying to get this thing going. No voltage is going to the AC clutch. I hot-wired it, the clutch engages, and it creates cold air. I ran the test on the AC amp according to the FSM and it may be bad, so @70sguy was kind enough to pull one and the loop connector I think may be missing (A25). This is a 1990 HDJ81 VX ltd with center cooler, no rear AC, and push button with auto air.
According the the wiring diagram in the Chassis FSM (RM184E), the AC fuse sends 12v to 3 things: the AC switch (H15#17) and AC amp (A19#14) and the normally closed starter cut relay (A28). The AC switch (H15#6) and AC system amp (A39#13) send 12v to AC amp (A19#4). I assuming that together the AC switch and AC system amp (for auto systems only) tell the AC amp to close (via A19 #1 & #2) the mag clutch relay (A21), which sends 12v to the normally closed AC water temp cut relay (A20) and straight on to the mag clutch. I had to pull the dash to remove and test the two relays (A21 & A28) on top of the cooler box (who puts relays in a place that can't be reached by anyone but tinker bell???) and they are fine. Everything I've tested gets ~12v except the AC switch (H15#6) which only reads 4.5v; the AC amp (A19#4) gets 12v, so I'm assuming the AC system amp (H39#13) is making this up. I can't measure what goes into or out of the relays and can't test relay A20 without pulling the cooler box, which may be my next step. Clear as mud?
The wiring diagram I am using shows a short connector (A25) which may be missing, if it's even needed. It may be a JDM thing. A few of the wire colors don't match up and according to the diagram, without this A25, no voltage should be going to the AC amp (A19#4) at all, but it is. I doubt that the PO removed the dash and pulled this, but you never know.
So, I can only find three things that may be bad:
1. AC amp may not be really closing the circuit although I read 12v at those leads(#1 ). replacing this
2. water temp relay (A20) could be bad. test this if AC amp is good
3. the short connector (A25) is missing. on the way but should I put it in?
Any other ideas?
Also, I am swapping this to R134A. I am assuming there are o-rings that will need replacing at each junction, so I'm waiting to pull the cooler box until the end if I can. Any info on doing the swap would be appreciated.
According the the wiring diagram in the Chassis FSM (RM184E), the AC fuse sends 12v to 3 things: the AC switch (H15#17) and AC amp (A19#14) and the normally closed starter cut relay (A28). The AC switch (H15#6) and AC system amp (A39#13) send 12v to AC amp (A19#4). I assuming that together the AC switch and AC system amp (for auto systems only) tell the AC amp to close (via A19 #1 & #2) the mag clutch relay (A21), which sends 12v to the normally closed AC water temp cut relay (A20) and straight on to the mag clutch. I had to pull the dash to remove and test the two relays (A21 & A28) on top of the cooler box (who puts relays in a place that can't be reached by anyone but tinker bell???) and they are fine. Everything I've tested gets ~12v except the AC switch (H15#6) which only reads 4.5v; the AC amp (A19#4) gets 12v, so I'm assuming the AC system amp (H39#13) is making this up. I can't measure what goes into or out of the relays and can't test relay A20 without pulling the cooler box, which may be my next step. Clear as mud?
The wiring diagram I am using shows a short connector (A25) which may be missing, if it's even needed. It may be a JDM thing. A few of the wire colors don't match up and according to the diagram, without this A25, no voltage should be going to the AC amp (A19#4) at all, but it is. I doubt that the PO removed the dash and pulled this, but you never know.
So, I can only find three things that may be bad:
1. AC amp may not be really closing the circuit although I read 12v at those leads(#1 ). replacing this
2. water temp relay (A20) could be bad. test this if AC amp is good
3. the short connector (A25) is missing. on the way but should I put it in?
Any other ideas?
Also, I am swapping this to R134A. I am assuming there are o-rings that will need replacing at each junction, so I'm waiting to pull the cooler box until the end if I can. Any info on doing the swap would be appreciated.
