a/c compressor runs all the time

780 bertone · Post by **780 bertone** » 26 Jun 2009, 14:54

1989 Volvo 780 Bertone.The compressor clutch does not disengage,it will run continuously as long as the a/c switch is on.If you turn the swich off it will shut off. Thanks for any suggestions.Have replaced a/c low side pressure switch,and relays under the dash.

Post by **vegasjetskier** » 26 Jun 2009, 19:28

Are you getting cool air out of the vents? Does the car cool down to the temp you have chosen?

780 bertone · Post by **780 bertone** » 28 Jun 2009, 09:51

Yes cold air is coming out the vents it will run continuously,burnt up clutch on old compressor,replaced compressor,charged system,same problem clutch will not disengage.

Post by **vegasjetskier** » 28 Jun 2009, 10:18

780 bertone wrote:Yes cold air is coming out the vents it will run continuously,burnt up clutch on old compressor,replaced compressor,charged system,same problem clutch will not disengage.

I can't find a wiring diagram for your car, but perhaps you have a stuck relay.

780 bertone · Post by **780 bertone** » 28 Jun 2009, 10:21

Replaced relays under the dash.

Post by **billofdurham** » 28 Jun 2009, 11:55

ECC? Is the control unit showing any fault codes?

Bill.

780 bertone · Post by **780 bertone** » 28 Jun 2009, 14:08

No fault codes

Post by **vegasjetskier** » 28 Jun 2009, 15:11

780 bertone wrote:No fault codes

Do you have ECC or manual control?

780 bertone · Post by **780 bertone** » 30 Jun 2009, 18:36