johnsoj0266

After I swapped a JDM H22A into my '99 Accord I noticed that my A/C was not cooling properly while in slow traffic situations. I have found out that my fans are not coming on when the A/C compressor is on. A/C is good when traveling on the highway. I have confirmed that both fans do come on when the water temp is high enough to require the cooling from the fans. So there is not an issue with the relays, grounds or with any wiring within the related wiring harnesses.

I am running a chipped P28 ECU out of a '94 Civic. As mentioned, the compressor clutch will activate, just the fans will not. It appears that the ECU is not recognizing the A/C switch when activated to turn on the fans, but will turn on the compressor.

I have spent many hours tracing the wiring and troubleshooting, using ECU pin-outs and schematics. I am at a loss here. I have even confirmed that the conversion harness was wired correctly.

Please help if you have any experience with this swap and related A/C problems.

PTV6

If push came to shove you could always hard wire one of the fans into your ac switch.

johnsoj0266

I had thought of that and like you said, was only going to do that if push came to shove.

What I have done is to splice the signal relay ground (coil side) of the A/C Clutch to the Radiator Fan Control together. This way the fan relay coils get grounded when the clutch relay coil does. This is a work around, but it is fairly clean since I just spliced the two wires in the conversion harness. Therefore, no changes to OEM wiring to cause problems if I pull the H22A for some reason. The only issue left is that the engine RPM is not bumping up to compensate for the additional load. The engine is not stalling out, but I just don't like it.

I feel there must me a mis-match somewhere in the conversion harness and/or pinouts that I am not seeing. For now I have good cold air though and that is what matters. If I find something else down the road, I will post it.