Removing A/C from a 730 vehicle

timsiford at hushmail.com timsiford at hushmail.com
Fri Feb 16 16:59:24 GMT 2001


Short: I removed the A/C from my car.  Any special work needed to BIN?  
I really don't think so but I want to confirm.

Long: I removed the condenser, accumulator, and A/C lines but left the wiring 
harness and dashboard control intact.  The 730 has one input for A/C information 
(BC9, Dk Green Wire, Circuit #59).  This wire runs to ....

1) the compressor clutch (off to ground)
2) then to the A/C high pressure switch 
3) then to the Pressure cyling swtich
4) then to the A/C control switch
5) Fuse
6) Ignition

Do all 730 wiring harnesses contain Circuit #59 (even the 1LE without A/C)? 
 I know there aren't separate BINs for A/C and non A/C cars.  The BIN works 
with both cars.

Furthermore, Changes to the BIN, IMO don't seem to be necessary since the 
circuit is never really closed until the A/C control switch (dash switch) 
is in the 'on' position.   1LE cars don't have the A/C control switch and 
can never close the circuit (if they do get circuit #59 in their wiring 
harness?).  Correct?  I am asking because there is A LOT of code in the 
ANHT_HAC that is dependent on A/C clutch on/off and A/C pressure ... I just 
want to be -sure-.  

Next question ... Diacom reports A/C Clutch status and A/C Request status. 
 How can it report 2 values when there is only one ECM input?  My guess 
is that both parameters will always read the same.  True?  But, I looked 
at the HAC and even though it refers to A/C Clutch almost all of the time 
there are a couple of references to A/C head pressure.  

Tim


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