The complete automotive resource for buyers, sellers, and owners like you.
Car, Truck and SUV Forums at Roadfly
+ Bentley Forums
+ BMW Forums
+ Cadillac Forums
+ Chevrolet Forums
+ Ferrari Forums
+ Jaguar Forums
+ Lamborghini Forums
+ Lotus Forums
+ Mercedes-Benz Forums
+ Maserati Forums
+ MINI Forums
+ Porsche Forums
+ General Discussion
+ Marketplace Forums
Re: how can you tell ... (archive)

[ Follow Ups ] [ 7-series (E32) Message Board ] [ Msg. Board FAQ ]

Posted by Max Fretter (NZ) on January 04, 2001 at 17:07:09:

In Reply to: Re: how can you tell ... posted by Bryan Garner on January 04, 2001 at 16:07:08:

The outside temp. is in the 60's and before it was worked on their was no freon in the system and the clutch was comming on. The pulley turns but the clutch doesn't the air comming out of the vents is cool not cold when I turn the temp. all the way down

Thought for now... Is the aux fan in front of the radiator spinning?

This might be a clue as it's supposed to spin as soon as the compressor cuts-in... from the schematic I've got (735 but it's got all the non-engine specific extras shown so it should be relevant) the aux fan "normal speed" relay (in the aux fuse box by the cruise control servo) is enabled off the same control line out of the AC control unit as the compressor relay (schematic doesn't say where that is!)...

Of course, the fan could also be having problems from what I've read on the list.

The compressor feed AFTER the compresor relay goes to a "high pressure switch" - if that's open, no clutch power. After that the line goes to the clutch, and there is also a take off to the Motronic Control Unit (presume to prepare the idle speed control to maintain idle if necessary under the AC load). Could your AC guys have overpressured the system on filling? (or is there a control valve in the freon loop not opening and so the clutch is being held open by the HPS to protect the system... this stuff's not simple, eh?)

Good hunting.

Follow Ups:

[ Follow Ups ] [ 7-series (E32) Message Board ] [ Msg. Board FAQ ]
Questions, comments, or problems, please visit the Roadfly help desk. Logo © 1997 - 2018 Jump Internet Inc. All rights reserved.