Air Con system.

Uncle Dean · 5th October 2020, 08:49

First off I understand that there is alot written on here about the aircon system, I have read most of it and now gotten myself confused slightly.

I recently bought a 2003 75 2.0 cdti Tourer, in which the aircon didnt work, it was suggested that it maybe just needed a refil as the last documented refil was 8 years ago.

I took the car into a well known retailer for their free aircon check, they blamed the compressor but also put a dial onto the airccon pipes which showed a green pressure reading, indicating that there was gas inside.

Now i have carried out the ATC self check that came up with FC 00.
the cooling fan behind the gril does not operate.
the compressor is not jammed and rotates freely, but does not engage.
I have checked the engie bay fuses and all good, also swapped the black relay for fog light one and all good there also.

I have not yet checked the Trinary switch, or bypassed it.

I cant find the wiring diagrams anywhere so have just ordered the Rave disc from Rimmers.

Do the fans control box need to operate to feed power to the aircon system? Indicating possibly just one fault.
will the aircon operate without the fans?, indicating that i may have 2 faults.

Any help will be appreciated.

Dean

trikey · 5th October 2020, 10:07

The aircon should work even if the cooling fan doesn’t, the only issue will be over pressurising when the car is stationary.

Uncle Dean · 5th October 2020, 12:18

Quote:

Originally Posted by trikey

The aircon should work even if the cooling fan doesn’t, the only issue will be over pressurising when the car is stationary.

Thanks for the reply, I guess that means I have 2 faults to diagnose.

Uncle Dean · 5th October 2020, 12:22

The rain eased off this aft so have played around a bit more.

By bypassing the trimary switch I can activate the high speed fan.
Also at about 2 oclock inside the grille I can see a resistor fixed to the fan almost in an upright position, looks silver to me but could be wrong.

does this help at all?

Yorkshire GOC · 5th October 2020, 12:43

Quote:

Originally Posted by Uncle Dean

The rain eased off this aft so have played around a bit more.

By bypassing the trimary switch I can activate the high speed fan.
Also at about 2 oclock inside the grille I can see a resistor fixed to the fan almost in an upright position, looks silver to me but could be wrong.

does this help at all?

So you have a 2 speed fan and the silver resistor you see is a classic failure point on these cars with a 2 speed set up - you need to replace with the uprated gold resistor - they are normally on e bay but dont see one currently

macafee2 · 5th October 2020, 12:56

Quote:

Originally Posted by Yorkshire GOC

So you have a 2 speed fan and the silver resistor you see is a classic failure point on these cars with a 2 speed set up - you need to replace with the uprated gold resistor - they are normally on e bay but dont see one currently

I think Jules sells them

macafee2

trikey · 5th October 2020, 12:57

Quote:

Originally Posted by Yorkshire GOC

So you have a 2 speed fan and the silver resistor you see is a classic failure point on these cars with a 2 speed set up - you need to replace with the uprated gold resistor - they are normally on e bay but dont see one currently

I have a few tucked away somewhere..

Sent from my iPhone using Tapatalk

Uncle Dean · 5th October 2020, 13:10

Thanks again Trikey and all for the advice, found a resitor online so ordered it ready for my next day off that should hopefully fix the fan, now onto the aircon.

Rain back on up here in Scotland so it will have to wait a bit longer, hope to fix it in next 2 weeks as driving to Spain and it would be nice to arrive non sweaty.

Arctic · 5th October 2020, 14:43

Quote:

Originally Posted by Uncle Dean

Thanks again Trikey and all for the advice, found a resitor online so ordered it ready for my next day off that should hopefully fix the fan, now onto the aircon.

Rain back on up here in Scotland so it will have to wait a bit longer, hope to fix it in next 2 weeks as driving to Spain and it would be nice to arrive non sweaty.

This may help when the resistor arrives to fit it.

https://www.the75andztclub.co.uk/for...d.php?t=216734

SD1too · 5th October 2020, 16:41

Hi Dean,

The "second" fault you mention will most likely be loss of refrigerant gas due to lack of use. I'd recommend that you don't return to the "well known retailer" who blamed the compressor and uses a gauge marked in green (and presumably red as well).

Instead Google a mobile automotive air conditioning specialist in your area for a professional job. It will be money well spent in the long run.

Once your system is fully working, make sure that you run the air conditioning at least once a month all the year round to prevent the gas leaking out again.

Quote:

Originally Posted by Uncle Dean

... also swapped the black relay for fog light one ..

By the way that black relay with a fan logo on it is for the interior heater blower not the air conditioning/radiator fan.

Simon

5th October 2020, 08:49	#1
Uncle Dean Regular poster Rover 75 Tourer Join Date: Aug 2020 Location: Edinburgh Posts: 43 Thanks: 15 Thanked 24 Times in 11 Posts	Air Con system. First off I understand that there is alot written on here about the aircon system, I have read most of it and now gotten myself confused slightly. I recently bought a 2003 75 2.0 cdti Tourer, in which the aircon didnt work, it was suggested that it maybe just needed a refil as the last documented refil was 8 years ago. I took the car into a well known retailer for their free aircon check, they blamed the compressor but also put a dial onto the airccon pipes which showed a green pressure reading, indicating that there was gas inside. Now i have carried out the ATC self check that came up with FC 00. the cooling fan behind the gril does not operate. the compressor is not jammed and rotates freely, but does not engage. I have checked the engie bay fuses and all good, also swapped the black relay for fog light one and all good there also. I have not yet checked the Trinary switch, or bypassed it. I cant find the wiring diagrams anywhere so have just ordered the Rave disc from Rimmers. Do the fans control box need to operate to feed power to the aircon system? Indicating possibly just one fault. will the aircon operate without the fans?, indicating that i may have 2 faults. Any help will be appreciated. Dean Last edited by Uncle Dean; 5th October 2020 at 09:12..

5th October 2020, 10:07	#2
trikey Premium Trader Rover 75 Join Date: Nov 2010 Location: Devon Posts: 33,763 Thanks: 8,837 Thanked 14,831 Times in 8,030 Posts	The aircon should work even if the cooling fan doesn’t, the only issue will be over pressurising when the car is stationary. __________________ Lest we forget..

5th October 2020, 12:22	#4
Uncle Dean Regular poster Rover 75 Tourer Join Date: Aug 2020 Location: Edinburgh Posts: 43 Thanks: 15 Thanked 24 Times in 11 Posts	The rain eased off this aft so have played around a bit more. By bypassing the trimary switch I can activate the high speed fan. Also at about 2 oclock inside the grille I can see a resistor fixed to the fan almost in an upright position, looks silver to me but could be wrong. does this help at all?

5th October 2020, 13:10	#8
Uncle Dean Regular poster Rover 75 Tourer Join Date: Aug 2020 Location: Edinburgh Posts: 43 Thanks: 15 Thanked 24 Times in 11 Posts	Thanks again Trikey and all for the advice, found a resitor online so ordered it ready for my next day off that should hopefully fix the fan, now onto the aircon. Rain back on up here in Scotland so it will have to wait a bit longer, hope to fix it in next 2 weeks as driving to Spain and it would be nice to arrive non sweaty.