[David R.]

Hello,
I'm the happy owner of a very nice 1988 MulsanneS since one year. This is my first one and my first post on this forum too !
Few days ago, I lost the complete air conditioning fan system: nothing happen when I turn the fan speed button located on the dashboard; whatever the position from eco to high is, there is desperately no air flow...as if the button remains on off...
I checked the fuses F1-A1 and F3-A6, both are ok.
I guess I'm not the first one who is experiencing this failure. Could anybody help me to fix this ?
Thank you in advance.
David

 

[Jim Walters]

If you turn the switch to "defrost" do the fans come on?

 

[FLYER34]

See this thread, I had the same issue on my 1988 Corniche.

Air Conditioning Test Procedures - 1989 Bentley Turbo

The air conditioning does not operate on my 89 Bentley. I have performed most of the test procedures as set out in the Work Shop Manuel (TSD 4700) using a multi-meter and I have not uncovered anything that indicates a problem. In doing the test for the fans control circuit I can faintly hear the...

www.rollsroyceforums.com

 

[David R.]

Hello Jim,
unfortunately on "defrost" position fan doesn't come on.

 

[David R.]

Hello Flyer34, I'll perform different checks mentioned in the thread you've indicated to me and will let you know. Thank you.

 

[Jim Walters]

OK if no defrost fans that indicates a main power issue so double check the fuses, make sure that they are tight in the clips and not corroded. They can get overheated and melt the plastic base then the clips won't hold the fuse tight. Check all the relays, swap with good known and check the sockets and spades on them for corrosion. Do the relays behind the left front shock tower under the bonnet and the ones in the row below the fuses. Also it could be the main ground for the AC ECU, it is under the carpet on the right side just below the radio console. It is common for this ground connection to get corroded and stop all operation of the AC. It will NOT be the 44° sensor, the failure of it is a common cause of AC failure but the defrost function will work even if that sensor is faulty.

 

[David R.]

Hello Jim, I removed corresponding fuses (F1-A1 & F3-A6), cleaned them with specific liquid and replace them. Now it works ! Thank you very much for the info ! The only issue I have now is that front passenger glass is moving when activating passenger door button but not from driver door button. I'll check the corresponding wire and driver door switch.