NX Brad

Well, my wife is just about ready to trade my Hot-Rod off; if I cant fix the AC.

I have cleaned all the relays and fuse; that was a problem at the beginning of the summer. I fixed the display thanks to the site and now I have luke warm air coming out the driver side and cold air on the passenger side. I also just added a can of freon. It got a lot colder after that. The compressor is coming on when it is switched on, and it doesn't cycle off, and on, like it was the pressure switch. My wife informed me that their was a time yesterday; just for a minuet, it blue cold, at the end of the day. I'm wondering if the controller is going out. Please help I really love my Zo6

P.S. I tried to look for old post!

RoccoC5

Sounds like the driver's side actuator is bad. I had the same issue and replaced the left actuator and all was good.

Are you showing a few HVAC DIC codes? Probably B0446, B0361, and/or B0363?

Have a look at this: http://vette.tnreeds.com/actuator/actuator.htm

patton

do a search ,pull 2 fuses etc. keep trying this or pull dash

NX Brad

My wife already went to work Ill work on it tonight.

NX Brad

Well, I pulled up the codes and didn't see the ones that it said I should see. I went and did the mod and it still does the same thing. I cleaned all the contacts on the relays and fuses, I reset the codes, I put some freon in the system. and I just about broke my back trying to get the screws back in the module. I don't know where to go from here. It blows cold out of the passenger side and warm out the driver side. I'm willing to pull the dash out if I have too. My wife just went on a trip for 7 hours and It was the s***t's. HELP

bestvettever

Hi, relax, it's not as difficult to troubleshoot as you may think.
1, You need to check the actual pressures in the AC system, to see if the system is properly charged. They should read approx 35psi @2000rpm's @ 90 degrees temp with about 40% humidity. There's a chart posted by plasticfan that has all the pressures and temps. You need to use guages to do this, as just indiscriminantly adding refrigerant is like shooting in the dark. Once you know the pressures are right go on to 2(This is an important first step, because if the system is short no other repair will fix it).
2, Do the fuse #27 recalibration--turn driver side temp dial to 60, pass side to straight up 12 o clock, ign off, pull fuse 27 ip fusebox, wait no less than 60 full seconds, replace fuse and listen to hear the actuator doors recalibrating, run ac system at the temps set and see if you don't get cold air both sides. If not step 3
3, At this point the highest probability is that your driver side actuator motor needs to be replaced. Although there is a slim probability that your control head is malfunctioning, but you said that you repaired it, so I'm assuming that you did it correctly.
SEE BELOW for a diagnostic and instructions to replace the actuator.
Good Luck Post if you need any further help
++++++++++++++++++++++++++++++++++
Air Temperature Control Inoperative CJ2
Air Temperature Control Inoperative <<CJ2>> Step
Action
Value(s)
Yes
No

DEFINITION: Driver's side air temperature control is inoperative. No DTCs are set. The driver's side temperature control button is the master setting for both the LH and RH electric actuators. The following table will diagnose either of the following two conditions: (1) The driver's side temperature control button is adjusted and neither the LH or RH electric actuators respond accordingly. (2) The driver's side temperature control button is adjusted and only the RH electric actuator responds. LH actuator is inoperative.

1
Were you sent here from the HVAC System Check (CJ2)?
--
Go to Step 2
Go to HVAC System Check (CJ2)

2
Disconnect the LH electric actuator connector.
Turn the ignition switch to the ON position.
Use a DMM to measure the voltage between terminal 5 of the LH electric actuator connector and ground.
Is the voltage within the specified range?
10.0-14.0V
Go to Step 4
Go to Step 3

3
Check the HVAC MiniFuse® #18 for an open circuit.

Is the fuse open?
--
Go to Step 17
Go to Step 18

4
Connect the DMM between terminal 10 of the LH electric actuator connector and ground.
Turn the ignition switch to the ON position.
Measure the available voltage at terminal 10 of the LH electric actuator connector.
Is the voltage within the specified range?
4.0-6.0V
Go to Step 6
Go to Step 5

5
Locate and repair an open or a high resistance in CKT 1791 between the HVAC control head and the LH electric actuator connector.

Is the repair complete?
--
Go to HVAC System Check (CJ2)
--

6
Are both the LH and RH electric actuators inoperative when the driver's side temperature control is adjusted?
--
Go to Step 12
Go to Step 7

7
Connect the DMM between terminal 9 of the LH electric actuator connector and ground.
Turn the ignition switch to the ON position.
Measure the available voltage at terminal 9 of the LH electric actuator connector.
Is the voltage within the specified range?
4.0-6.0V
Go to Step 10
Go to Step 8

8
Backprobe the HVAC control head connector terminal C8 with the positive lead of the DMM.
Connect the negative lead of the DMM to ground.
Turn the ignition switch to the ON position.
Measure the available voltage at terminal C8 of the HVAC control head connector when it is connected to the HVAC control head module.
Is the voltage within the specified range?
4.0-6.0V
Go to Step 9
Go to Step 15

9
Locate and repair an open or high resistance in CKT 733.

Is the repair complete?
--
Go to HVAC System Check (CJ2)
--

10
Disconnect the HVAC control head connector.
Connect a fused jumper between terminal 5 and terminal 6 of the LH electric actuator connector.
Turn the ignition switch to the ON position.
Use a DMM to measure the voltage between terminal C7 of the HVAC control head connector and ground.
Is the voltage within the specified range?
10.0-14.0V
Go to Step 12
Go to Step 11

11
Locate and repair an open or high resistance in CKT 1199.

Is the repair complete?
--
Go to HVAC System Check (CJ2)
--

12
Turn the ignition switch to the OFF position.
Connect the DMM between terminal D1 of the HVAC control head connector and terminal 7 of the LH electric actuator connector.
Measure CKT 1798 for continuity between the HVAC control head connector and the LH electric actuator connector.
Is CKT 1798 continuous?
--
Go to Step 14
Go to Step 13

13
Locate and repair an open or a high resistance in CKT 1798.

Is the repair complete?
--
Go to HVAC System Check (CJ2)
--

14
Reconnect all of the components back to their respective connectors.
Connect the scan tool to the diagnostic link connector.
Turn the ignition switch to the ON position.
Select HVAC readout parameters on the scan tool.
Rotate the LH side temperature control **** between full hot and full cold.
Check for the LH MIX MTR POSITION REQUEST and the LH MIX MTR POSITION FEEDBACK signal on the scan tool.
Does the HVAC control head send a change in position request to the LH actuator but the LH actuator sends no feedback response to the HVAC control head?
--
Go to Step 16
Go to Step 15

15
Replace the HVAC control head.

Is the repair complete?
--
Go to HVAC System Check (CJ2)
--

16
Check for any poor connections.
Check for any binding conditions.
If OK, replace the LH electric actuator.
If through testing it was found that both electric actuators were inoperative, then replace both the LH and RH electric actuators.
Is the repair complete?
--
Go to HVAC System Check (CJ2)
--

17
Locate and repair a short to ground in CKT 41.

Is the repair complete?
--
Go to HVAC System Check (CJ2)
--

18
Locate and repair an open or a high resistance in CKT 41.

Is the repair complete?
--
Go to HVAC System Check (CJ2)
--
++++++++++++++++++++++++++++++++++
SEE BELOW
Temperature Actuator Replacement LH
Removal Procedure




Remove the front floor kick-up panel. Refer to Kick-Up Panel Replacement - Front Floor in Interior Trim.
==================================
Trim Pad Replacement - Instrument Panel (I/P) Upper
Removal Procedure




Remove the console. Refer to Console Replacement .
Remove the IP accessory trim plate. Refer to Trim Plate Replacement - Instrument Panel (I/P) Accessory .
Remove the driver knee bolster trim panel. Refer to Trim Panel Replacement - Knee Bolster .
Remove the instrument panel compartment. Refer to Compartment Replacement - Instrument Panel (I/P) .
Remove the windshield defroster grille. Refer to Defroster Grille Replacement .
Insert the DRL and sunload sensors, if equipped, into the nearest openings in the windshield defroster duct. Moving the sensors into the defroster duct provides additional clearance to remove the trim pad.
Remove the windshield side garnish moldings. Refer to Windshield Side Garnish Molding Replacement in Stationary Windows.
Remove the screws retaining the upper trim pad to the defroster duct.
Remove the screws retaining the upper trim pad to the LH and RH hinge pillars.



Remove the screws retaining the IP cluster bezel to the upper trim pad.
Remove the screws retaining the upper trim pad to the driver knee bolster outer bracket and the center support bracket.
Remove the screw retaining the upper trim pad to the passenger SIR bracket.



Tilt the steering wheel to the lowest position.
Lift the rearward edge of the upper trim pad approximately 5 cm (2 in) to provide clearance for the air distribution duct located on the underside of the trim pad.
SLOWLY pull the upper trim pad away from the windshield while guiding the tabs on the LH and RH side of the trim pad past the hinge pillars.



Disconnect the hazard warning switch electrical connector.
Remove the upper trim pad from the vehicle.
Installation Procedure




Connect the hazard warning switch electrical connector.



Install the IP upper trim pad into position.
Tilt the forward edge of the trim pad down slightly.
SLOWLY begin to move the trim pad into position while guiding the tabs on the LH and RH side of the trim pad past the hinge pillars.
Locate the trim pad by guiding the alignment notch on the underside of the pad onto the alignment pin on the dash panel.
Lower the rearward edge of the pad into place.
Remove the DRL and sunload sensors, if equipped, from the openings in the windshield defroster duct and position above the trim pad.




Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.


Install the screws retaining the upper trim pad to the windshield defroster duct. Tighten
Tighten the IP upper trim pad to windshield defroster duct screws to 1.9 N·m (17 lb in).

Install the screws retaining the upper trim pad to the LH and RH hinge pillars. Tighten
Tighten the IP upper trim pad to LH and RH hinge pillar screws to 2.5 N·m (22 lb in).





Install the screws retaining the upper trim pad to the driver knee bolster outer bracket, the center support bracket and the passenger SIR bracket. Tighten
Tighten the IP upper trim pad to driver knee bolster outer bracket screw to 1.9 N·m (17 lb in).
Tighten the IP upper trim pad to IP center support bracket screws to 1.9 N·m (17 lb in).
Tighten the IP upper trim pad to passenger SIR bracket screw to 1.9 N·m (17 lb in).
Install the screws retaining the IP cluster bezel to the upper trim pad. Tighten
Tighten the IP cluster bezel to IP upper trim pad screws to 1.3 N·m (12 lb in).

Install the windshield side garnish moldings. Refer to Windshield Side Garnish Molding Replacement in Stationary Windows.
Install the windshield defroster grille. Refer to Defroster Grille Replacement .
Install the instrument panel compartment. Refer to Compartment Replacement - Instrument Panel (I/P) .
Install the driver knee bolster trim panel. Refer to Trim Panel Replacement - Knee Bolster .
Install the IP accessory trim plate. Refer to Trim Plate Replacement - Instrument Panel (I/P) Accessory .
Install the console. Refer to Console Replacement .
==================================


Remove the cover from the I/P electrical center.
Remove the HVAC CON (HVAC controls) MiniFuse® #27 from the I/P electrical center.
Remove the I/P upper trim pad. Refer to Trim Pad Replacement - Instrument Panel (I/P) Upper in Instrument Panel, Gauges and Console.
Remove the instrument panel cluster (IPC) to steering column bracket retaining screws.
Reposition the IPC to better access the LH temperature valve electric actuator.



Remove the LH side window defogger outlet duct - lower.
Remove the push-in retainer.
Use a twisting motion to release the defogger outlet duct - lower from the windshield defroster duct, then from the defogger outlet duct - upper.




Remove the inside air temperature sensor aspirator duct.
Depress the duct retaining tab and remove the duct from the ignition switch housing bracket.
Use a twisting motion to release the duct from the duct muffler.




Remove the inside air temperature sensor aspirator duct muffler. Use a twisting motion to release the duct muffler.



Disconnect the electrical connector from the LH temperature valve electric actuator.



Remove the two screws retaining the LH temperature valve electric actuator.
Remove the electric actuator.
Installation Procedure




Position the LH temperature valve electric actuator, then align the slots in the electric actuator driver to the flats on the LH temperature valve shaft.
Slide the electric actuator driver onto the shaft, while aligning the actuator locating hole to the forward alignment pin on the HVAC module case. The actuator driver should completely seat onto the temperature valve shaft and be the actuator mounting holes should be flush with the mounting bosses on the HVAC module case.

Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.


Install the two LH temperature valve electric actuator retaining screws. Tighten
Tighten the LH temperature valve electric actuator retaining screws to 1.5 N·m (13 lb in).





Connect the electrical connector to the electric actuator.



Install the inside air temperature sensor aspirator duct muffler. Use a twisting motion to secure the duct muffler.



Install the inside air temperature sensor aspirator duct.
Use a twisting motion to secure the duct to the duct muffler.
Install the duct retaining tab to the ignition switch housing bracket.




Install the LH side window defogger outlet duct - lower.
Use a twisting motion to secure the defogger outlet duct - lower to the defogger outlet duct - upper, then to the windshield defroster duct.
Install the push-in retainer.




Install the instrument panel cluster (IPC) into position.
Install the IPC to steering column bracket retaining screws. Tighten
Tighten the IPC to steering column bracket retaining screws to 3.5 N·m (31 lb in).

Install the I/P upper trim pad. Refer to Trim Pad Replacement - Instrument Panel (I/P) Upper in Instrument Panel, Gauges and Console.
Install the HVAC CON (HVAC controls) MiniFuse® #27 to the I/P electrical center.
Install the cover to the I/P electrical center.
Install the front floor kick-up panel. Refer to Kick-Up Panel Replacement - Front Floor in Interior Trim.

NX Brad

Ok I must have a leak. The pressure was at 21Lb and now it at 39lb after a can of 134a . The vents are blowing cold and I haven't recalibrated the system I'm going next week to a friend and find the leak; then I will recalibrate the system.

It is common to have one side blow hot and the other cold when it's low on freon?

byronhunter

It is common to have one side blow hot and the other cold when it's low on freon?[/QUOTE]

Yes, it is very common, but only if right is the cold side.

BBz06Fan

Thread worked like a charm. AC is back and I'm thrilled!

americanretrodave

I’m a new member, I recently picked up a 97’ Vette. I bought it with the heater blasting on the driver’s side and the passenger’s side ice cold. I figured it was the driver’s side actuator and once home, without reading anything here, I jumped into replacing it. I figured out how to remove all the center console pieces and then I took off the lower panel under the steering. It took awhile, but I finally found out where the actuator was and proceeded to remove it; it wasn’t easy coming up from the driver’s side floor board but a long extension helped, I managed to get it out. I replaced it and discovered it didn’t correct the problem. The old actuator was bad, so I was stumped. I used a micro light on a long stem and ran it through the vent to the driver’s side door, the travel didn’t look good. So I took out the new actuator, (a pain if anyone has done this, especially without taking out the dash which I assume would have been easier) and tried reaching up to move it by hand. The travel didn’t feel right, but I couldn’t feel anything in it’s way. I re-installed the actuator a second time and still, the heat was blowing. This is what brought me to this site and this thread. My next move was to check the codes, and you guessed it, I found 99-HVAC BO361 and BO441. I set the passenger side control at 12:00 and the driver’s side at 60 degrees, I then removed the three fuses described here, re-installed them and I had cold air, but it still wasn’t as cold as I felt it should be. I then tried the heater and once again I had hot air on the driver’s side. Now, again reading from this forum, felt I must be low on freon. I took it in and sure enough I was low, yet, after filling it, I still had hot air on the driver’s side. I once again did the fuse removal thing and it was cold again. But when I tried the heater, it wouldn’t come back and work correctly, no air, only heat. Once again, I took the actuator out (I hate this job). I then took it apart and mine wasn’t like the picture on the attached link above. My gears were different. I marked the gears, and then moved a little gear what I thought would move the larger gear two notches counter clock wise. Once again, I reinstalled that wonderful actuator. I did everything again, and again, it didn’t work correctly. I (feel my pain) removed that actuator a fourth time, this time, being a little more aggressive, I moved the large gear two notches counter clock wise and put it back together. I reinstalled it, set the controls, removed the fuses and finally, I have ice cold air on both sides, my heater works great, (both sides) and everything works as it should. For only owning this car for less than a week, I feel I’ve learnt a lot about it. The numbers on my control unit are okay when my headlights are on but in the day time, they are extremely hard to read, I may have a problem with that coming up, but for right now, it’s all good.

This isn’t my first Vette, I’ve had a 58’, a 60’, three 62’s, a 64’, a 66’, a 74’ and now this 97’ (the first one that wasn‘t a convertible). I still have one of the 62’s.

bdiddo

Jeez...I am having the same issue. From the number of us with this problem or had this problem, sounds like faulty part. It is still above 100 degress in the Phoenix, AZ area. - need that a/c!

dmarkshark

You said the freon is low,did you put some freon in with dye? Then you can check everyting under the hood for leaks. You can get everything you need at Autozone (or any other auto store), freon,glasses,and light.You can also check the evaporator by putting a white towel under the drain tube area on the passenger side ( if it is cold enough for the water to collect and drain)and check it for dye. There are only so many places it can leak. Then you will know what to fix before you start throwing everything at it like I find myself doing at the moment. Another question would be how fast are you losing the freon in the first place, since you put freon in and it got cold?

Benny Tatum

Thanks so much for your input. Very benefical

C6Vette18

Sorry for bringing this back from the dead. but i just had thise same issue.

What do you all mean by set the passenger side dial to 12:00? My passenger also reads in degrees.

Also, where is the fuse box located?

Thank you.

Got uid0

Most likely meaning if you have passenger side temperature control ***** to set them so that the blend door is not set to be in the full position hot or cold.

Blend door actuators are a common failure point.