oops hit send too early.
So yes please can you send me the one you have on the understanding that it might or might not work. Please let me know your email so that I can Paypay you whatever you want to charge for it
Peterwhight@yahoo.co.uk
No charge, happy to help. If turns out not needed just post it back. If you email me address I’ll pop in post tomorrow .
2 Likes
That is the high pressure switch as the sightglass is behind it. You can disconnect and put a cable across the pins in the plug and check it operates the a/c or just temporary plug in the replacement switch from Rutland surfer to see if the system works without fitting to the pipework. Its a lot of work to fit ( decant refrigerant again, change, pressure test , vacuum the system and recharge ) just to be 100% sure the switch is the issue.
Hi Peter,
That is so kind of you. If it doesn’t work of course I will return it. If it does, can I make a small donation to a charity of your choice?
My details
Tony Worsdall
23 Cypress Road
Woodley
RG5 4BD
Thanks once again
Posted today. Sorry for delay, been busy at work and couldn’t get to post office before. Hope it sorts it for you.
No apologies necessary, and thank you once again, I am away till Monday so timing works well. I will let you know how it goes. Thanks again Tony
Hi there, well the part is fitted but still no joy. there is power to the cockpit switch and when its turned on the fan works and the engine speeds up momentarily, but it looks like the ECU is just not sending the signal to the compressor.
The conclusion I am being led towards is that the ECU has got freaked when the Compressor was changed (maybe the compressor was a little sticky) . Now, without getting in to the ECU I am a little stuck.
Seems I have two options 1) just not have AC in the car (bit inconvenient) in the winter as it mists up quick) 2) get a connection made directly from the switch to the compressor, which might be a bit risky if the compressor malfunctions in future.
The compressor works if powered directly and the system is fully gassed.
Anyone know a technician that knows which pins on the ECU control the AC. (If I know these it possible to take the diagnosis further (after I have drilled out the screws)
All this is making me favour Option 1 as ECU fiddling sounds like an expensive hobby:-)
Assuming any 2.5 ECU will do the job like all 1.8 vvt 2.5s have the wiring loom 
I rescued an ECU, keys and locks from a parted out 2.5 vvt do not think it had AC . I’m in France until the weekend, but you are welcome to borrow them SOR if you want to try them out and can wait that long. I am just up the roadish near Watford. If interested PM me and I’ll see if can sort something out on Sunday 
I’m pretty sure there is no ecu involved in operation. I’ve fitted air con to 2 nb 1600s and never had to change ecus or plug anything in to them. It’s just switches and relays.
I would check relays and connections next. They are mounted behind near side headlamp and get a lot of exposure to moisture as behind air intake from wheel arch. On the one car I got system from the relays themselves had corroded and wouldn’t operate. The original relays are expensive for what they are but I got some for about a fiver each from Halfords (was a couple of years ago so may have gone up a bit since). Had to cut plugs off and wire in but straightforward enough . Wiring diagram in Haynes manual will show you wire colours.
2 Likes
For system to work there is a feed from blower fan switch, contact in pressure switch should be closed when system pressurised and there’s a temperature switch which should have a closed contact (I think this is the plug on air con matrix unit behind glove box).
Also looking at drawing compressor clutch power comes from a separate fuse from rest of system (except possibly 2nd cooling fan) so double check all fuses.
Drawing does show ‘power train control module’ and I confess I’ve no idea where this is, I never had to fit one just plugged in all the other bits, pressurised it and it worked.
1 Like
Hi there, thank you for such a kind offer but I think I will pass. I think I am in that position where I dont know enough about auto electrics to want to take on this job. I am suspecting its not the ECU, and if it is then I might just live without the AC. Thanks once again for reaching out, Tony
1 Like
Sounds logical to me. I have the haynes manual so will start looking at the relays again (I did check them before and they looked OK) I guess one could be shot without showing any external signs.
I think what I am getting form the technicians is their ‘best guess’ and to be fair they havent charged me for any of this as they have failed to get it working.
I cant see a temperature switch on the Haynes diagram ?
Going to have a good look tomorrow and will let you know how I got on.
As they have fitted the pressure switch you sent I have the one that was on my car originally. Happy to send it back to you?
Thanks for taking the time to help out. I am sure I will get there 
If you can send back but no rush, get it sorted first. Good luck
So You were right, two of the pins on the relays were corroded and one was out. Off to get some repairs and will ;et you know how it goes. Likely to be in a weeks time as I am away for a while.
Fingers crossed
1 Like
You are welcome Tony, in the light of subsequent posts it would appear you do not have an ECU problem, good luck with getting your a/c sorted.
I have been toying with the idea of collecting all the parts to fit an a/c unit to mine for six years now, somehow I do not think it’s going to happen.
Thanks once again and I will post the results of the next steps in resolving this for other members to follow
1 Like
So here are the suspected culprits. They looked OK at first glance but when I unbolted them they sort of fell apart! Sone judicious soldering to come . Will post results in a couple of weeks.
2 Likes
I’d buy new crimp terminals rather than try to solder it.
Something like this.
You’ll have to buy a crimp tool too if you don’t have one.
1 Like
Thanks for this Robbie. I agree, gonna have a word with the tech who is doing the work and suggest the crimp solution…