Re: AC Compressor wont come on

[jtrealty@xxxx]

In the description it was indicated that although the cooling fans 
cycled they didn't run continuosly with the a/c on. It was also 
indicated that there wasn't any power at the compressor. This leads me 
to believe that the low pressure switch is probably holding back the 
power due to a low pressure condition in the system. There is no high 
pressure switch although the manual mentions one. The cooling fans are 
supposed to cycle against the otterstadt switch in the coolant pipe 
but if the mode switch is in the A/C position and the low presssure 
switch is "on" it forces the cooling fans to run continuosly. If the 
A/C cylcles against the low pressure switch the fans might shut down 
if the otterstadst switch is satisfied. I think the fanzilla will 
force the cooling fans to run when the A/C switch is on regardless of 
the otterstadt or low pressure switch. Just because the cooling fans 
run you cannot assume the power is comming from the mode switch. The 
fact that there was no power at the compressor clutch means the 
cooling fans were not being run by the A/C circuit. There is no need 
to worry electricaly about the compressor clutch since it won't run if 
no power is present.(You can always just do a continuity check of 
the coil on the compressor clutch) The trouble is in the circuit 
before that. I think that your understanding is not taking into 
account that the cooling fans can be run from 2 different circuits, 
the otterstadt switch and the A/C compressor circuit.
David Teitelbaum
vin 10757


--- In dmcnews@xxxx, dherv10@xxxx wrote:
> David, As per the diagram, The voltage comes thru #10 fuse the
> goes thru the mode switch then goes thru a low pressure and
> some cars may also have a high pressure switch.

[moderator snip]