Is the HVAC control module the same as the engine PCM?

5speednightstand · Post by **5speednightstand** » Mon Mar 19, 2012 1:00 pm

I now have a disc of the vibes service manual, and it is the worst one I have seen. (and I have seen quite a few) No section I can find that has component locations. On the circuit for the ac clutch, it is fed from the HVAC control module. Of course it does not say where that is, and I wonder if it is just integrated into the PCM.

tpollauf · Post by **tpollauf** » Mon Mar 19, 2012 1:51 pm

Quote, originally posted by 5speednightstand Â»I now have a disc of the vibes service manual, and it is the worst one I have seen.Just curious if it is an electronic version of these ......................... Lots of information BUT as I already found out, several major errors. While removing the entire interior, seats, panels, etc ..... most of the sketches & description are of the first gen Vibes (2003-08) and NOT of the 2009-10 models Hopefully if/when I need to resource these books the next time they will be more accurate

dgekiere · Post by **dgekiere** » Mon Mar 19, 2012 5:13 pm

HERE ARE A FEW MORE GM DOCUMENTS TO MAYBE HELP. THE ONE SHOWS WHERE THE MODULE IS LOATED

Attached files HVACMODULEREPLACEMENT.docx (129.3 KB)

dgekiere · Post by **dgekiere** » Mon Mar 19, 2012 5:14 pm

AND THE OTHER FOR DIAGNOSING THE COMPRESSOR NOT ENGAGING

Attached files HVACCOMPRESSORDOESNOENGAGE.docx (17.4 KB)

Nightstandvibe · Post by **Nightstandvibe** » Tue Mar 20, 2012 1:53 am

DG, I owe ya a beer, thanks for the help. I bought a factory service manual on dvd on ebay, and it is full of errors. Like switching out the relay for the clutch, when there is no relay in the circuit. It references the HVAC control module, yet does not have any component locations that I can find. Really appreciate it.(I do have a paper copy of the matrix electrical manual on the way, hoping that is a lot better.)Off to the bone yard to see if I can scarf up a module. (Taking bets on how much at the dealer!)

vibenvy · Post by **vibenvy** » Tue Mar 20, 2012 10:27 am

Quote, originally posted by tpollauf Â»Lots of information BUT as I already found out, several major errors.I'm really disappointed with this information. I was all set to order the service manuals, but I guess I'll put the $200.00+ towards something more useful .

Water boy · Post by **Water boy** » Tue Mar 20, 2012 1:41 pm

Quote, originally posted by J_TO_ENVY Â»I'm really disappointed with this information. I was all set to order the service manuals, but I guess I'll put the $200.00+ towards something more useful .Invest in this site?

journeyforce · Post by **journeyforce** » Sat Mar 24, 2012 8:19 am

What about a Matrix shop manual? I would think only a few things would be GM exclusive? I don't even think the PCM is different since the Matrix and Vibe both had the same computer reflash so that leads me to believe the Matrix and Vibe both share the same PCMI buy all my parts from Toyota and I don't even let the GM dealership(and it was the one the car was bought from originally) change the oil let alone any repairs. I get my oil changed at ToyotaIt is a rebadged toyota with different body panels. So I would think a shop manual for the Matrix would work well for your needs

5speednightstand · Post by **5speednightstand** » Sun Mar 25, 2012 11:49 am

Well, it gets better. The a/c is intermittent, or at least worked once this week. But can not get it to again. Have tried mashing the button, turning on defrost, etc, multiple times. To my way of thinking that leaves the module or low charge. But would it work at all with low charge in the system?

Nightstandvibe · Post by **Nightstandvibe** » Mon Mar 26, 2012 1:44 pm

Holy Shnikes! The control module (AKA the "amplifier") is over $300!!!!!!! Damn.

Stumped · Post by **Stumped** » Mon Apr 30, 2012 7:54 am

Same guy here, had to get new user name because I lost sign in.

Well, the stealer so far has charged me $95 for a "diagnosis" fee, and yet has no diagnosis. Pissed would be putting it easy. They tell us they need "6 to 8 hours of labor" to tear apart the dash and get to it. ?????????? major (removed). It is an electrical problem of some sort, there is no voltage at the compressor clutch. The sensor for the pressure is $408 DOLLARS. The compressor control module is only 158 or so. I guess I will start shot gunning parts at it.

The links that are posted for directions are no longer valid. I need them again. The plan was maybe GM would give us some help on the bill, and so we took it there for help. Waste of $95. Please do not ever go to Bill Rapp's stupid store in SYR for ANYTHING.

Stumped · Post by **Stumped** » Mon Apr 30, 2012 7:59 am

dgekiere, could you PM me with the pages you linked? I have the schematic, but the flow chart and module location I still need. Maybe because of the new user name I am not able to PM you?

6 to 8 hours to diagnose? I am steaming.

Stumped · Post by **Stumped** » Mon Apr 30, 2012 10:13 am

New pressure sensor from dealer: $408 + tax.

From Amazon.com: $191. Hope this fixes it. Pressure sensor is saying -44psi, which is pretty implausible. It can only be the sensor or the control module.

Stumped · Post by **Stumped** » Mon May 07, 2012 6:43 pm

Just to follow up, bought the pressure sensor on amazon.com, replaced and re-charged and it works AWESOME!

Furious with the dealer, they just want to suck a grand out of anyone's pocket for an ac repair. They scanned it for 100+ bucks, noted an improbable response from the pressure sender, and then said it needed 5 or 6 hours for further diagnoses. I really feel sorry for people who have no clue and have to fall helplessly into the stealers hands. They are damn thieves. They wanted $408 for the pressure sensor BTW, and you can get it online for less than half that.

Is the HVAC control module the same as the engine PCM?

Is the HVAC control module the same as the engine PCM?

Re: Is the HVAC control module the same as the engine PCM? (5speednightstand)

Re: Is the HVAC control module the same as the engine PCM? (5speednightstand)

Re: Is the HVAC control module the same as the engine PCM? (dgekiere)

Re: Is the HVAC control module the same as the engine PCM? (dgekiere)

Re: Is the HVAC control module the same as the engine PCM? (Nightstandvibe)

Re: Is the HVAC control module the same as the engine PCM? (J_TO_ENVY)

Re: Is the HVAC control module the same as the engine PCM?

Re: Is the HVAC control module the same as the engine PCM?

Re: Is the HVAC control module the same as the engine PCM?

Re: Is the HVAC control module the same as the engine PCM?