Climate control not working

alpa

Member
Messages
169
  1. You can replace your A/C control with any control unit of the EFI biturbo car: 200/400, Ghibli, QP4. They are all compatible even though there are 3 versions.
  2. The usual failure is the L293 component. It's overloaded by construction.
The link below is my old post about that. It's in French but google will help you:
3. I suggest to repair your control unit because it feature a built-in diagnosis, unlike Ghibli and older versions.
 

Arvid

Member
Messages
158
Hi Alpa,

Thanks for great information. Interesting that the panels are interchagable. I did not know that nor that it was possible. But I opt for keeping the original panel as it's what suits the interior the best.

I studied the QP Evo electric diagrams in the WSM yesterday and it is as you suggest the IC that is the main suspect. I have talked back and forth with Gareth and I'm going to send him my panel for repair and testing. It will be in capable hands and I can consentrate on other tasks meanwhile :)
 
Messages
388
That Bruno colour was the original colour of mine also. But for the respray I opted for Prugna, as opposed to sticking strictly with originality.

Separate but related. How far did you go with the respray out of interest?

Only I’ve got a car I’m thinking about changing the colour of and don’t really want to go as far as ‘engine out’ but not sure if I’ll be happy or not with bits of the old colour cropping up here and there.
 

Ewan

Member
Messages
6,757
It was a full bare metal respray. So, doors, bonnet and boot lid off, glass and trim out, badges and lights off/out, etc. Though not the engine bay, as in Ferrari's of this era that is all black anyway. But anywhere that had been painted the exterior colour, was stripped right back and repainted.
From memory it came in it at about £25k, including new badges, rubber trims, new rear screen, new rear lights and front lenses, and a few other sundries.
 
Messages
388
It was a full bare metal respray. So, doors, bonnet and boot lid off, glass and trim out, badges and lights off/out, etc. Though not the engine bay, as in Ferrari's of this era that is all black anyway. But anywhere that had been painted the exterior colour, was stripped right back and repainted.
From memory it came in it at about £25k, including new badges, rubber trims, new rear screen, new rear lights and front lenses, and a few other sundries.

Yes, that’s the way to do it if you’re going to. The car I’m toying with the idea of changing the colour of is a lovely thing (Jaguar XJR6 Supercharged the original straight six) but not worth that kind of investment.

98057
 
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dt95aac

Member
Messages
116
3. I suggest to repair your control unit because it feature a built-in diagnosis, unlike Ghibli and older versions.

Ghibli units also feature the built-in diagnostics which show the temperature readings of the various sensors etc, unless you meant something different.
 

alpa

Member
Messages
169
Ghibli units also feature the built-in diagnostics which show the temperature readings of the various sensors etc, unless you meant something different.

Certainly not all. Probably last Ghibli but on my GT '97 there is no diag
 

qpv8evo

New Member
Messages
22
Hi there Gareth,

I didn't think FB was good for anything but I was wrong. I found Gareth :)
Thank you Arvid.
You will have your unit back very soon so you can get your car back on the road.
Can't wait to see some pics.
 

Arvid

Member
Messages
158
Thank you for the swift service Gareth. I'll get back to you when it arrives and installed.
 

henris42

Junior Member
Messages
86
  1. You can replace your A/C control with any control unit of the EFI biturbo car: 200/400, Ghibli, QP4. They are all compatible even though there are 3 versions.
  2. The usual failure is the L293 component. It's overloaded by construction.
The link below is my old post about that. It's in French but google will help you:
3. I suggest to repair your control unit because it feature a built-in diagnosis, unlike Ghibli and older versions.

Wow that is great info, I did now know that one. I've had some issues with my unit, the previous "mechanic" had hard-wired the compressor clutch to fuel pump relay, presumably there were issues before. The unit was superficially fine, but I'm suspecting issue on clutch output pin since they hacked it. I haven't yet got time to check, I'm still now finalizing the megasquirt ECU change, A/C will connect to it as well. What I did manage to do when I opened it up was to change lights from lamps to LED:s... :)

The part on your french article is fascinating on interchangeability of the MCU. If you have extra one with diag functionality, I'd be happy to clone it and make available little upgrade! Also there probably is a pin-compatible upgrade to L293 (just my experienced gut feeling, to be researched).
 

alpa

Member
Messages
169
The part on your french article is fascinating on interchangeability of the MCU. If you have extra one with diag functionality, I'd be happy to clone it and make available little upgrade! Also there probably is a pin-compatible upgrade to L293 (just my experienced gut feeling, to be researched).

If you are able to clone a 68705 MCU eprom then why not.
 

Masermartin

New Member
Messages
1
Hi there, I know this is an older thread but the problem for me is new. The aircon on my QP IV, 2.8 manual (1995) stopped working from one second to the next. The control panel is dead. I have checked the underbonnet relay and by bypassing can hear the compressor click and see it whirring. Well it looks like the control panel is the culprit since it does not seem to be getting any power from the dash. My question is it easy to remove the panel which surrounds it? - I do not want to damage the wood surround. I can then check the connections as suggested in the pdf on this threat. Car is in daily use at least in summer and is great fun to drive. Martin from Hamburg in Germany.
 

alpa

Member
Messages
169
You'll need to remove the radio. Then the wood panel could be held by screws under the radio, or screw on the very bottom of the panel, depends on the cars. No more than 4 screws.