Auto air auto all the time

I posted sopme time ago re: that my climate control would blow AC cold even on 'Econ' and 'Vent'. While working on the car this morning I saw the compressor kick on even while the climate control was 'Off'. It just arbitrarily kicks on and off at will.

My question is: Where do you think this 'will' is coming from?

FYI, I have done the reset process to it as far as the self diagnostic. Is there another process I'm not aware of?

Help please...Premium fuel is at $1.95 and I am a salesman on the road now.

Money waving goodbye.

Randy ii

[Ron Mummert]

[QUOTE]Originally posted by svxeno
[B]I posted sopme time ago re: that my climate control would blow AC cold even on 'Econ' and 'Vent'. While working on the car this morning I saw the compressor kick on even while the climate control was 'Off'. It just arbitrarily kicks on and off at will.


You've discovered the SVX "Fla" button, Randy. It's not labled, but all cars delivered to your state will run the A/C all the time from March to October. The AARP approved this feature for its Sunshine State clientele.

Enjoy.

Ron.

[lee]

Randy,

I have an idea, but can't say how likely it is to be correct.

The transistor managing the A/C relay to the compressor in my ECU died. It works normally by receiving a signal from the climate control module, and switching the A/C relay to ground (when A/C is desired) to trigger the relay. Also, when at WOT, it drops the ground, cutting out the A/C until you let off the gas for a bit more power. In my case, it failed to provide a ground to the A/C relay regardless of what the climate control module said to do, so the A/C never came on. I don't know what kind of failure modes transistors can take, but if yours is intermittently & improperly providing a ground to the wire, that will kick in the A/C compressor regardless of what the rest of the system is doing.

To troubleshoot, I suppose you could tap the wire from the ECU to the relay and hook up a VOM, watch the signal, etc. to see if my idea has any merit.

I ended up not replacing the ECU, but made a voltage follower circuit to circumvent the ECU control of the compressor - but it cost me the WOT cutout of A/C - like I ever drive that way anyway.

Alternately, but along the same lines, the wire itself between ECU and A/C relay could be chafed and is making intermittent ground. That would seem harder to check for an intermittent problem.

Originally posted by lee
Randy,

I have an idea, but can't say how likely it is to be correct.

The transistor managing the A/C relay to the compressor in my ECU died. It works normally by receiving a signal from the climate control module, and switching the A/C relay to ground (when A/C is desired) to trigger the relay. Also, when at WOT, it drops the ground, cutting out the A/C until you let off the gas for a bit more power. In my case, it failed to provide a ground to the A/C relay regardless of what the climate control module said to do, so the A/C never came on. I don't know what kind of failure modes transistors can take, but if yours is intermittently & improperly providing a ground to the wire, that will kick in the A/C compressor regardless of what the rest of the system is doing.

To troubleshoot, I suppose you could tap the wire from the ECU to the relay and hook up a VOM, watch the signal, etc. to see if my idea has any merit.

I ended up not replacing the ECU, but made a voltage follower circuit to circumvent the ECU control of the compressor - but it cost me the WOT cutout of A/C - like I ever drive that way anyway.

Alternately, but along the same lines, the wire itself between ECU and A/C relay could be chafed and is making intermittent ground. That would seem harder to check for an intermittent problem.

Lee,

Thank you very much. That will be an adventure to track down.

Ron,

Thank y...uh...yeah...right.


Randy ii

ps: May be a moot point. See general SVX gab.

[SSSVX]

randy ii,
u solved your AC probs?

yeah, the premium here today go up to 1.89.....

what kind of gas mileage you get on your SVX?
what kind of gas mileage you get on your saturn?
for city and highway.....

if you want to save some gas money/mthly and take care of
your engines running better... you could email your cellphone# to
gbw5@yahoo.com....i have an add-on thing for your vehicles..
so can let you know more....if it doesn't work on...get your
money back. i have them on my vehicles and svx...working
good... thanks..

I really think you have a bad climate control panel Randy.


Dave