2004 GXP . A/C blowes cold when in park or reverse , When drive is selected you can here the a/c clutch drop out and the fans stop( cooling fans ). As soon park or rev is selected the a/c clutch engages andthe cooling fans will start a few seconds latter and the air will get cold and stay that way(hvac works normal)( tested for 20 min ).
The hvac control pannel , dim and the ipm have been replaced. All with the same result NO AIR in drive. What will inhibbit a/c in drive ???

_________________
2004 Black GXP 157,00 Mi.
1988 corvette coupe 5.7 auto 133,000 Mi.
1984 Corvette coupe 5.7 auto 248,00 Mi.
1999 SUPPERDUTY 7.3 auto 4X4 ( GM retrieval truck )328,250 Mi.

Difficult to answer. Is the rest of the HVAC system working - the blower motor, and other HVAC controls. Have you scanned the car to look for codes. This can be a number of things from shorts to loose or bad connectors, to a bad PCM. Have you brought the car to a GM dealer to work on it?

_________________
bobgto65

2004 Bonneville GXP 62,000 miles purchased 04/13
2009 G8 GXP PBM, M6 9580 miles, no mods, sold 08/15
2009 G8 GT SBM 36,000 miles, modded 430 whp
2002 Bonneville SSEi 203,200 miles (sold 3/2014)

There are no powertrain fault codes. As for taking it to the dealer that would be the last resort.

_________________
2004 Black GXP 157,00 Mi.
1988 corvette coupe 5.7 auto 133,000 Mi.
1984 Corvette coupe 5.7 auto 248,00 Mi.
1999 SUPPERDUTY 7.3 auto 4X4 ( GM retrieval truck )328,250 Mi.

Definitely a tough call on this one, not something I have ever seen come around before. It does sound like a short of some sort though, best bet might be to find a local auto electric shop and have them look at it.

_________________
Ryan

2003 Bonneville SSEi - The Black Mirror SOLD!
2002 Bonneville SE - The Mutt Complete 2004 SLE interior, drivetrain, and body harness swap, ECC swap, HUD swap, black GXP wheels, GXP headlights and tinted tails - SOLD
2003 BMW 540i M Sport, 2001 BMW X5 4.4i, 2010 GMC Acadia, 2017 Grand Design Imagine 3150BH
1982 Cutlass Supreme - The fun one

As I said in the orignal post, The system works as it should when in park , Netural or reverse. I would think a bad p/n switch would show up in the pcm. I dont have a toool to scan the body ecm's yet.

_________________
2004 Black GXP 157,00 Mi.
1988 corvette coupe 5.7 auto 133,000 Mi.
1984 Corvette coupe 5.7 auto 248,00 Mi.
1999 SUPPERDUTY 7.3 auto 4X4 ( GM retrieval truck )328,250 Mi.

It wouldn't necessarily show in scans as bad and that may not the the culprit anyway.

_________________
Ryan

2003 Bonneville SSEi - The Black Mirror SOLD!
2002 Bonneville SE - The Mutt Complete 2004 SLE interior, drivetrain, and body harness swap, ECC swap, HUD swap, black GXP wheels, GXP headlights and tinted tails - SOLD
2003 BMW 540i M Sport, 2001 BMW X5 4.4i, 2010 GMC Acadia, 2017 Grand Design Imagine 3150BH
1982 Cutlass Supreme - The fun one

Start by checking the connectors to the transmission and HVAC components under the hood and the one to the PCM for any signs of corrosion. Take each one apart and replace any that are bad. I have found a few connectors on my '02 that were corroded and had to be replaced. Check all the wire harnesses for any signs of damage that may cause shorted wires inside.

_________________
bobgto65

2004 Bonneville GXP 62,000 miles purchased 04/13
2009 G8 GXP PBM, M6 9580 miles, no mods, sold 08/15
2009 G8 GT SBM 36,000 miles, modded 430 whp
2002 Bonneville SSEi 203,200 miles (sold 3/2014)

I have checked the pcm connectors thet were ok , moving on to the rest this weekend.

_________________
2004 Black GXP 157,00 Mi.
1988 corvette coupe 5.7 auto 133,000 Mi.
1984 Corvette coupe 5.7 auto 248,00 Mi.
1999 SUPPERDUTY 7.3 auto 4X4 ( GM retrieval truck )328,250 Mi.

I wonder if it could be sensing a "load" issue. Typically when you go WOT (100% throttle), it shuts the clutch off and essentially freewheels the compressor. I wonder if the switch/sensor that does this is at fault, makeing it think it's at full load, in effect disengaging the compressor clutch.

_________________


Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*

Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
2004 Pontiac GTO: Impulse Blue Metallic/Black/M6: lots 'o mods, 415 RWHP / 405lb/ft RWTQ!
2006 Cadillac STS-V: Light Platinum Metallic/Light Gray/A6 - Spectre CAI, Magnaflow exhaust, Speed Inc. tune, 412 RWHP / 472lb/ft RWTQ

Daily Drivers:
2019 Chrysler Pacifica Limited: Mommy's new RGC
2015 Chrysler Town & Country Limited Platinum: Kids new RGC
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck

sorry these 2 posts came up before I finished and I don't know how to delete them.

_________________
bobgto65

2004 Bonneville GXP 62,000 miles purchased 04/13
2009 G8 GXP PBM, M6 9580 miles, no mods, sold 08/15
2009 G8 GT SBM 36,000 miles, modded 430 whp
2002 Bonneville SSEi 203,200 miles (sold 3/2014)

`

_________________
bobgto65

2004 Bonneville GXP 62,000 miles purchased 04/13
2009 G8 GXP PBM, M6 9580 miles, no mods, sold 08/15
2009 G8 GT SBM 36,000 miles, modded 430 whp
2002 Bonneville SSEi 203,200 miles (sold 3/2014)

I have the shop manuals. . The fuse for the A/C clutch relay is 15 amps and then is controlled by Relay 32 under the hood controls. The output from the relay switch is a green wire that runs to the A/C compressor. Accordingly, the way you describe your problem, the green wire should be hot when the car is in park or neutral, but in drive it should not be reading any voltage. The control relay has a is a dark green/white wire that runs to the PCM. The PCM has another relay inside that closes to ground the coil in relay 32 and energizes the switch fo the clutch. Are you with me so far?

For some reason, the PCM is not closing the relay when the car is in drive. The PCM send a signal to the transmission as to what position the sensor is in. There is a white wire from connector C3 on the PCM to C100, a round connector with 20 pins at the left rear lower side of the engine that includes this wire, then to the transmission. The relay control switches for the cooling fans and the A/C clutch are on connector 1 from the PCM. So it is unlikely that any of these wires cross. CMNTMXR57 may have a good point that at WOT, the compressor will shut down and so will the cooling fans.
This is controlled by the throttle position sensor on the top side of the engine to the left of the throttle body and has 3 wires running to it. Tap into the 3 wire connector. The gray wire is 5V reference and the black is the low reference. Check the 5V reference to make sure the voltage is there. Both go to the PCM. The voltage across the blue wire will vary with the throttle position, from 5V down to close to zero. Hook your DMM up with the red lead to the blue wire and the black lead to ground and move the throttle and see if the voltage is changing. If not, the sensor is bad and replacing it may solve your problem.

_________________
bobgto65

2004 Bonneville GXP 62,000 miles purchased 04/13
2009 G8 GXP PBM, M6 9580 miles, no mods, sold 08/15
2009 G8 GT SBM 36,000 miles, modded 430 whp
2002 Bonneville SSEi 203,200 miles (sold 3/2014)

I would think a faulty TPS would set a P0122 or 0123 code( circuit low or hi input ). However I an still checking the engine compartment connectors. If bobgto65 could post or E mail the electrical drawing this may help in the troubleshooting.

_________________
2004 Black GXP 157,00 Mi.
1988 corvette coupe 5.7 auto 133,000 Mi.
1984 Corvette coupe 5.7 auto 248,00 Mi.
1999 SUPPERDUTY 7.3 auto 4X4 ( GM retrieval truck )328,250 Mi.

It could. But you would almost need a scan tool to see the voltage it is getting at those moments in time. I believe 4.5 - 4.7 volts is standard GM TPS sensor reading at WOT.

I suppose you could somehow work a multi-meter into the connections and test it too, but that is a little more involved and would need two people. One to take the readings and one to cycle it through the gears.

_________________


Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*

Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
2004 Pontiac GTO: Impulse Blue Metallic/Black/M6: lots 'o mods, 415 RWHP / 405lb/ft RWTQ!
2006 Cadillac STS-V: Light Platinum Metallic/Light Gray/A6 - Spectre CAI, Magnaflow exhaust, Speed Inc. tune, 412 RWHP / 472lb/ft RWTQ

Daily Drivers:
2019 Chrysler Pacifica Limited: Mommy's new RGC
2015 Chrysler Town & Country Limited Platinum: Kids new RGC
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck

I plugged in the scan tool and the TPS reads as it should Near 1vdc at idle and 4.xx at wot.
Tps is good. I have looked at the connectors under the hood and cleaned all that had any thing to do with engine or the AC.
I put the car in drive ( with the wheels chocked ) and wiggle checked all the wiring I could reach. I disassembled both fuse blocks to check for corroded terminals (all good).
Does anyone have ant other ideas ???

_________________
2004 Black GXP 157,00 Mi.
1988 corvette coupe 5.7 auto 133,000 Mi.
1984 Corvette coupe 5.7 auto 248,00 Mi.
1999 SUPPERDUTY 7.3 auto 4X4 ( GM retrieval truck )328,250 Mi.

When it is in drive, does the heat work and the blower motor? I own a exercise equipment store in an old car dealership and the current owner has been there fixing cars for 18 years. I will check with their mechanics tomorrow to see if they have any other ideas. I did not see anything in the shop manuals in the AC troubleshooting guide about a problem like this.

My only other thought right now....
The A/C Clutch relay is controlled by the PCM. There is a dark green/white stripe wire going from the micro relay on the underhood fuse block to the PCM Connector C1 pin 56 (on one of the outside corners of the connector). When the relay is turned on, the voltage on the dark green/white wire should be close to zero. When the relay is off is should be 12-14 volts. If you can tap into this wire and check the voltage while the car is in reverse or park, you can watch the voltage cycle as the relay is turned on and off. If the voltage is always reading 12-14 with the car in drive, then the relay will not turn on. This may indicate a bad PCM. You can try pulling the PCM fuse to do a factory reset and see if the problem goes away. You already checked the PCM connectors and replaced the IPM, DIM, and AC Control Module. We are running out of things to try. The PCM controls this with transistors that ground the circuit. There is programming in the PCM to turn it on or off depending on several other conditions and some of that data comes over the data bus from the IPM and HVAC module. I'm still having problems tying this into the position of the shifter. ugh.

_________________
bobgto65

2004 Bonneville GXP 62,000 miles purchased 04/13
2009 G8 GXP PBM, M6 9580 miles, no mods, sold 08/15
2009 G8 GT SBM 36,000 miles, modded 430 whp
2002 Bonneville SSEi 203,200 miles (sold 3/2014)

Mechanics had no clue. They could not understand how the two events can be related. If nothing else works, it may boil down to replacing your PCM.

_________________
bobgto65

2004 Bonneville GXP 62,000 miles purchased 04/13
2009 G8 GXP PBM, M6 9580 miles, no mods, sold 08/15
2009 G8 GT SBM 36,000 miles, modded 430 whp
2002 Bonneville SSEi 203,200 miles (sold 3/2014)

You and me both. If not the PCM, then a bad compressor/clutch could be it too.

The problem is, this is not a text book issue. I can't say I've ever seen anything like this in my years of service.

_________________


Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*

Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
2004 Pontiac GTO: Impulse Blue Metallic/Black/M6: lots 'o mods, 415 RWHP / 405lb/ft RWTQ!
2006 Cadillac STS-V: Light Platinum Metallic/Light Gray/A6 - Spectre CAI, Magnaflow exhaust, Speed Inc. tune, 412 RWHP / 472lb/ft RWTQ

Daily Drivers:
2019 Chrysler Pacifica Limited: Mommy's new RGC
2015 Chrysler Town & Country Limited Platinum: Kids new RGC
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck

Iwill try the PCM reset. I do,t think the clutch is bad because it works fine in the other modes ( Park,N Rev ).

_________________
2004 Black GXP 157,00 Mi.
1988 corvette coupe 5.7 auto 133,000 Mi.
1984 Corvette coupe 5.7 auto 248,00 Mi.
1999 SUPPERDUTY 7.3 auto 4X4 ( GM retrieval truck )328,250 Mi.

The PCM reset had no effect. Installed a macto scan tool , No stored or active codes in any of the systems.
I am going to look at the wiring from the PCM to the AC clutch relay. I am leaning to the side of a bad PCM.
Stay tuned there is more to come...

_________________
2004 Black GXP 157,00 Mi.
1988 corvette coupe 5.7 auto 133,000 Mi.
1984 Corvette coupe 5.7 auto 248,00 Mi.
1999 SUPPERDUTY 7.3 auto 4X4 ( GM retrieval truck )328,250 Mi.