Wiring A/C

mdoyle · Post by **mdoyle** » Sun Mar 25, 2007 6:52 pm

Just looking for any information on how to wire in the A/C compressor clutch in a swapped car. I know there is the option in K Pro to use the VTEC oil pressure switch as an alternate signal for the a/c clutch.

What plug/pin is the VTEC oil pressure switch on the engine harness, does that go directly to the a/c compressor, and is there anything else that needs to be done for it to work properly?

mdoyle · Post by **mdoyle** » Mon Mar 26, 2007 8:45 am

Hondata wrote:The short answer is to connect ACS (from the vehicle harness) to VTP on the ECU.

When VTP (pin B9) is grounded the AC clutch will be switched on by the ECU. Note that you can't just ground B9 with a switch - the normal AC high/low pressure control, temperature control and fan control must be used, otherwise the AC compressor will be damaged. Look in your vehicle manual at the AC wiring section, or get the ETM.

I found this in another post. So basically I move the input wire for ACS (i'm assuming that stands for Air Condition System) that would have gone into the old ECU and move it to pin B9 on the K series engine harness, turn off the multiplexer, disable VTEC oil pressure switch under the VTEC tab in K Pro and select the Use VTP as altnerate a/c clutch engagement under the Misc tab in K Pro.

Am I understanding that correctly?

Post by **Hondata** » Mon Mar 26, 2007 9:58 am

Yes. ACC = A/C clutch, ACS = A/C switch (even through it is not actually the switch - see the above quote).

mdoyle · Post by **mdoyle** » Mon Mar 26, 2007 10:17 am

I've got the wiring for my car (1995 Accord), I see the pin outs for the FANH, ACS and ACC, do I need to do anything with the ACC and FANH wires, or do those work in conjuction with the ACS?

Guess i'm not understanding the post 100%. You say to ground the ACS, but if I just ground the ACS it will damage the compressor.

So the only thing that needs to be done wiring wise is move ACS on the chassis to B9 on the K series engine harness and i'm good to go. Or do I also have to wire in the ACC and FANH into the K series harness? And if so, which pin/plug do they go to?

mdoyle · Post by **mdoyle** » Mon Mar 26, 2007 12:11 pm

Ok, I think I got it.

On the Accord:
ACC goes to A15
Fan Control goes to A12
ACS goes to B5

RSX wire harness:
ACC goes to E18
FANC goes to B6

I believe all I have to do is this:
ACC 15 --> ACC E18 on K harness
FANC A12 --> FANC B6 on K harness
ACS B5 --> VTP B9 on K harness

Then set the correct settings in K Pro, and it all should work. Does that sound right to anyone?

mdoyle · Post by **mdoyle** » Fri Mar 30, 2007 7:49 am