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yeah i can hear it when i connect pin 9 so maybe i did pin 46 wrong?

i probed the wire as shown in the 2nd foto and i could hear the compressor clicking and i assume that means its working fine yeah?

i just wired the one next to power steering resevoir (light green/red stripe) one to earth for now lol

ill play around with it again when it dries up abit

if not i might just get 2 G U UP to do it for me.

Edited by whyte
yeah i can hear it when i connect pin 9 so maybe i did pin 46 wrong?

i probed the wire as shown in the 2nd foto and i could hear the compressor clicking and i assume that means its working fine yeah?

i just wired the one next to power steering resevoir (light green/red stripe) one to earth for now lol

ill play around with it again when it dries up abit

if not i might just get 2 G U UP to do it for me.

I have posted some photos showing the rb25 plug (near the power steering reservoir) and the wire which goes to pin 9. I have then taken a photo of the Rb25 plug connected to my R32 body loom plug and have shown which 2 wires need to be connected for pin 9 to be operational (I have used my test light).

Sounds like you found the right wire given you can hear the compressor cutting in. With the compressor operating you can turn the AC on and it should work. As a temporary fix, I would suggest running a wire from pin 9 wire to a switch which is connected to earth. This way you can manually switch the compressor on when you want to run the AC until you get the rest sorted.

When I get some time next week I'll take some photos of the plugs in the passenger foot well.

Cheers

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  • 1 month later...

im having the exact same problem ben. can u tell me what all the other wires in the rb25 plug on the strut tower are for? i have one hooked up for the injectors so far and am not sure what the other ones are for?

I had the same problem when I was installing the LEDs for the dash a month ago.

Didn't know how I fixed it but apparently I just unplugged everything on the dash and the AC unit then replugged it back it and el presto it works!!!

Same thing happened just last week when I was installing some buttons on the dash for my interior neons

So you might just wanna give that a go

I actually was intending to upload some more photos and further explanations over the christmas break but I only got as far as taking the photos. I'll try and put something together tonight if I get a chance.

I have put together a rough guide to wiring up an RB25 series 1 for an R32 GTS/T for another member (updated version of the one I sent you Mark), but its probably not really in laymans terms and only covers the main wires. Unfortunately I don't have the time at present to go into too much depth due to other commitments. When I eventually do get some free time I will try and simplify the guide and update it with pin information.

Cheers

Ok, I have attached a rough guide to wiring up the AC which addresses both pin 9 and pin 46. Once you have connected theses wires as instructed you need to carry out a couple of tests. I had to split the document into 2 because of size.

1. Measure the voltage at pin 46 whilst the AC is off, it should read about battery voltage. Likewise measure the voltage at pin 9 and it should also be battery voltage. If you don't have battery voltage at pin 9 then it is likely the pressure switch is open (low gas pressure) or a fuse is blown.

2. Switch the AC on and measure the voltage at pin 46 and it should read about 0-1V. If it is still battery voltage the ECU thinks the AC has not been requested to turn on and therefore will not earth pin 9 and thereby not switching on the compressor. This could be caused by a faulty climate control sensor and you should run the climate diagnostics to view any errors or false readings. A likely culprit (as I found recently) is a faulty intake air temp sensor which in my case read about -24degs. The climate control therefore obviously felt the compressor was not required due to the already "cold" outside air.

3. If you switch the AC on and the battery voltage at pin 46 drops to approx 0 but the compressor has not kicked in check the voltage at pin 9 and it should also be between 0-1V. If not then check the pressure switch and fuse as mentioned above.

I trust this helps.

Cheers,

Ben

Wiring_pin_46.doc

Wiring_of_Pin_9.doc

Edited by BH_SLO32

when aircon is on the revs are very low & stalls when coming to a stop.

how do i keep my revs up and the car from stalling ??

got a weird problem now, i got my aircon fixed then i tried to fix my wipers.

now i can only have one or the other. if i want aircon, i gotta take off the bridging wire from the wiper motor (turn wiper stalk to on) then turn on aircon as that turns the compressor on? that is a weird thing. if i want wipers, i gotta connect the bridging wire back up.

man this is giving me the shiets :(

Edited by whyte
when aircon is on the revs are very low & stalls when coming to a stop.

how do i keep my revs up and the car from stalling ??

The RB25's come with an FICD (Fast Idle Compensation Device) which bypasses more air around the throttle valve to increase revs when the AC is switched on. My guess is your FICD device is not hooked up. It is part of the AAC valve (2 pin purple plug). As the Rb20s don't have an FICD you will need to activate it with a relay triggered by the activation of the compressor. The alternative would be to increase your base idle to try and compensate for the drop in revs when the AC is switched on. The power feed to the FICD is from the yellow wire at the 8pin plug near the power steering reservoir. To increase the idle speed simply disconnect the AAC plug whilst the engine is idling and adjust the idle speed with the screw and then put the plug back on.

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