Removing A/C from a 730 vehicle

[rr]

Tim,

The reason that there is an A/C request & an A/C clutch, is that some masks
control the A/C clutch through the ecm. The dash switch tells the ecm that
you want A/C. And the ecm will control a relay to turn it on. And sometimes
off, like when in PE or high p/s pres.

Sometimes there is a pressure switch on the hi-pres line that will tell the ecm
to turn on the fan. If you get a fan running all the time, you may need to ground
this wire.

As far as I know, no ecm tables will need to be changed. I've yet to come across
a bin that requires changes for A/C. (of course there is always the exception).

BobR.

timsiford at hushmail.com wrote:

> 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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