no cool air from either front or rear vents

This sounds like a blend door actuator problem here are two guides to help us fix the problem.

https://www.2carpros.com/articles/replace-blend-door-motor

and

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

Please run down these guides and report back.

Hi-

Sometime my AC blows hot- as if it's in heater mode. It only happens sporadically. No matter whether I adjust the temp manually or set it on auto, it blows hot air. Oddly, the rear AC will still blow cold. I've tried turning the unti on and off and this doesn't work, but if it sits for awhile, chances are it's OK the next time. Very odd. Again, this doesn't happen every time, so I'm wondering if it's not an AC issue but an issue with the control gauges not communicating properly with the AC system, but have no idea. Any help would be much appreciated- thanks!

Hi dimattia23,

Thank you for the donation.

The problem is due to a fault with the air mix ( temperature actuator) and there is a possibility a trouble code is recorded. You can retrieve the trouble code with tha aid of a scan tool. Let me know the exact trouble if any found.

About a month ago I was on my way to Los Angeles. I had air conditioning on and all of a sudden I felt hot air coming from where the gas and brake pedal are. Then it started to blow hot air out of the driver side vent the big one and the passenger air side was fine. Turned off A/C and about two hours or so later it was fine again. Since then it has happened twice. Any ideas what can be wrong? Thank you

The drivers side blend door actuator need to be replaced. Here is a guide that will help you get the problem fixed and can get the part form Amazon:

https://www.2carpros.com/articles/replace-blend-door-motor

Check out the diagrams (below). Please let us know if you need anything else to get the problem fixed.

Cheers

Thanks for this post. It fixed my car! I love this site.

Over the past three weeks my A/C has been acting up. I first noticed it when it stopped blowing cold air and just blew air (temperature depending on outside temperature). I had it recharged and it blew cold air for about five days and then went back to what it was doing before. I have a dual A/C system and both sets of vents (driver and passenger) blow the same temperature, as well as the back passenger vents. It will blow heat if I crank the thermostat up, but not cold if set to sixty. Any thoughts on what it could be?

Have the gas level checked again. If the level is low, there is a leak in the system and you need to have that rectified to have cool air again.

The air conditioner in my 2003 Escalade has never worked properly and I have taken it in to Cadillac service every summer. Unless the vehicle is moving, it will not cool. During the hot weather it cools fine while rolling, but, stop at a light or in heavy traffic, it does not cool. As I am about out of my extended warranty period do you have any suggestions I can give the shop so they can fix it next week?

That can be low on 134a, an dneeding the pressure (high side) to be higher to make the cold air or it could be a problem with not enough air across the condensor (in front of radiator). Would be very helpful to know th eidling pressures of the a/c system to see what is going on

So the AC blows hot air through the front. If you do not put the AC button on but, put the temperature at 60 and why are driving the air does blow cold through both vents? When stopped the air blows hot in the front and cold in the back again with the AC button off and the temperature set for 60. we've tested the relay fuse and actually jumped the compressor and it seems to turn on, but it won't turn on without the jump. but the fuse seems fine because we switched it out with a similar fuse. When you look at where the condenser is and the pressure sensor, I have two wires coming out of the pressure system. Only one wire can plug into the condenser. Help?

Good afternoon,

There is a fan on the front of the motor and if that is not working and pulling air through the front of the radiator.

Can you see if the fan is turning with the engine running?

Roy

Fan Replacement

Tools Required
- J46406 Fan Clutch Remover and Installer
- J41240-5A Fan Clutch Wrench

Removal Procedure
1. Remove the upper fan shroud.



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2. Install the J46406 and the J41240-5A to the fan clutch.



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3. Remove the fan hub nut from the water pump in a counterclockwise rotation.
4. Lay the fan blade face down on a workbench.



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5. Remove the fan clutch bolts from the rear of the fan blade, if necessary.
6. Separate the fan clutch from the fan blade.

The problem that I am having is that my A/C is not working! When I turn it on the air blows only through the defrost and the air compressor does not come on when I push the A/C button on the computer climate control and nor does it switch from vent in face or to vents on the floor. I bypassed the relay switch and the compressor came on I even bought a new computer climate control and the same thing is happening I tried re-calibrating the system and still nothing when I had bypassed the relay switch I was able to charge it up it blew cold air only from the vents in the roof of the truck rear air I guess the fan blows hard it is just only coming out through the defrost. can anyone help? thanks

Hello,

It sounds like you have a blend door actuator that has gone out, here is a guide to help you get the problem fixed.

https://www.2carpros.com/articles/replace-blend-door-motor

It shows which blend door it for vent mode.

Please let us know what happens.

Best, Ken

Good morning Gentlemen. I have a 2002 Cadillac Escalade. My ac is blowing cold air in the front and hot air in the rear. When I took it to the dealer for a diagnostic they said my ac compressor is bad. I change the ac compressor, accumulator, orifice tube and the condensor. It is still blowing hot air in the rear. I don’t know what to look for any more can you help me out? What wrong with the rear ac? Thank you for you helps

I have the same problem... please someonse help!!! I replaced the compressor, put a vacuum on the system ( no leaks) and refilled, still nothing.

Hello, everyone!

Yes this is a problem with the rear ac blend door actuator that has gone bad and must be replaced, here is a guide and diagram on how to get the problem fixed.

https://www.2carpros.com/articles/replace-blend-door-motor

Please let me know if you need anything else to get the problem fixed.

Best, Ken

i had the same problem with my 2007 Escalade. The rear blend door actuator was on the window side of the unit. had to undo bolts and pull the blower unit to the inside enough to undo the actuators. Pain in the arse but better than removing the whole thing. Most models seem to have them easily accessble but not the 2007, not sure why. Anyway fixed the problem of cool air in the front and hot in the back. Now its all cool.

Great addition to this thread! Please feel free to help out whenever you are on the site :)

Cheers, Ken

I had my battery, alternator, belts (including fan belt) replaced at the same time. Now one of my AC controls is not working. Now the mode knob does not appear to be working....air only blows out as if the mode know were placed on the defrost position, however is will not switch to any other position when turning the knob. I was told by the service repair place that because the climate control is electronic and the battery and alternator were replaced it could take upto 200 miles for the car to reset it setting and recognize the correct climate control settings. Does this sound correct to you? Do you know of a reset method to get the mode know to work correctly again and recognize the various settings, (vent, bi-level, floor, blend, etc.)?

Tks.

If I am correct, your mode is on a button, and knobs control the driver and passenger temp. It should not take that long for the system to update. It should take minutes. There is an actuator recalibration procedure.

2002 Cadillac Escalade | Avalanche, Escalade, Suburban, Tahoe, Yukon (VIN C/K) Service Manual | HVAC | HVAC Systems - Automatic | Diagnostic Information and Procedures | Document ID: 774485
--------------------------------------------------------------------------------

Actuator Recalibration
The HVAC control module will relearn the actuator limits whenever power is disconnected and re-connected to the module.

Use the following steps to perform the calibration update:

Turn OFF the ignition.
Remove the battery positive voltage circuit fuse of the HVAC Control Module.
Important: The scan tool must be disconnected from the vehicle to properly perform the calibration procedure. If a scan tool is connected before this procedure is completed, then new calibration values will not be stored.

Important: Failure to wait 60 seconds will not allow the HVAC control module sufficient time to clear the old calibration values.

Wait 60 seconds.
Install the fuse.
Turn ON the ignition.
Wait 60 seconds before installing a scan tool.

There is also a couple bulletins that may apply.

#04-01-39-007: Loss of HVAC System Mode and/or Temperature Control (Replace HVAC Control Module) - (Jun 17, 2004)


Subject: Loss Of HVAC System Mode and/or Temperature Control (Replace HVAC Control Module)


Models: 2002 Cadillac Escalade, Escalade EXT

1999-2002 Chevrolet Silverado, Suburban, Tahoe

2002 Chevrolet Avalanche

1999-2002 GMC Denali, Sierra, Yukon, Yukon XL

2001 GMC Sierra C3

2002 GMC Sierra Denali

with Automatic HVAC System (RPO C68)




--------------------------------------------------------------------------------

Condition
Some customers may comment that they cannot control the HVAC system modes and/or the temperature. These concerns may be intermittent.

Cause
An HVAC control module logic lock-up may be the cause of these conditions.

Correction
Important: Prior to replacing the HVAC control head, review Corporate Bulletin Number 01-01-39-007 (SI Document ID #845221).

Replace the HVAC control module. Refer to the HVAC Control Module Replacement procedure in the HVAC System -- Automatic sub-section of the Service Manual.

Part Information
Part Number
Description

15126606


Condition
Some customers may comment that they cannot control the HVAC system modes and/or the temperature. These concerns may be intermittent.

Cause
There may be poor terminal contact and/or bent terminals in connectors C206 (RPO C68 automatic HVAC controls) or C296 (RPO C60 manual HVAC controls). Excessive tension on the wires due to the wiring harness being misrouted in the instrument panel carrier may cause these conditions.

Correction
Remove the Air Bag fuse.
Disconnect the steering wheel and instrument panel (IP) air bag connectors. Refer to the SIR subsection of the Restraints section of the Service Manual for connector locations.
Remove the IP upper trim pad.
Locate connector C206 (6 cavities) or C296 (8 cavities). The connector is attached to a metal brace on the far right side of the IP carrier above the IP air distributor duct.
Inspect the routing of the wiring harness to the connector. The proper routing of the wiring harness is above the air distributor duct with no tension on the terminals in the connector. The routing is improper if the wiring harness is below the air distributor duct with excessive tension on the terminals in the connector. The excessive tension may cause poor terminal contact, resulting in open circuits, in the connector. The wires may also pull the terminals out of the connector or pull out of the terminal itself.
If the harness is routed properly, contact Technical Assistance for further information.
If the harness is misrouted, remove the connector from the brace.
Disconnect the connector.
Perform a pin drag test on the female terminals.
Inspect the male terminals for straightness.
Inspect the wire to terminal connection to insure that no wires have pulled out of the terminals.
Reroute the wiring harness above the air distributor duct.
Firmly reconnect and reseat the connector.
Reattach the connector to the metal brace.
Reinstall the IP upper trim pad.
Turn Off the ignition and reconnect the steering wheel and IP air bags.
Reinstall the Air Bag fuse.
Turn ON the ignition and verify that the air bag light flashes seven times and goes out.
Clear any diagnostic trouble codes that may have been set.
Verify proper operation of the HVAC system mode and temperature controls.

2005 escalade rear hvac calibration that works! - on the rear auxiliary heater and air conditioning control module (located under rear panel on passenger side - directly rearward of rear door on passenger side) remove the red and grey connectors, then turn key on. Insert red connector, then insert grey connector. System will start calibration mode. Leave key on (approx. 3 min). This is the only method that worked on my system

2002 Escalade. Sometimes, the A/C suddenly stops blowing ice cold air, and starts blowing slightly cool air. Its the same at both the front and rear vents. I put a thermometer in the drivers side vent to track actual temperature coming out of the vent. When it's working, it blows around 45 degree air. When it's "not" working, it blows 78 degree air. Outside temp is always hot when this happens, like 95-105 degrees. But, sometimes it works fine when it very hot outside. I tapped into the A/C compressor wire and ran a small indicator light into the vehicle. So, the light comes on whenever the compressor is running. The compressor DOES run, I can see the clutch engage, a noticeable load hits the engine and the condenser fan turns on. When the vent temp runs up to 78 degrees, the compressor IS running. To eliminate the possibility of a heater valve issue, here's what I did: I turned off the A/C and moved the temperature control knob to the hottest setting. The vent temp went to 150 degrees (hot!). Then, under the hood, I put clamps on the input AND return lines for the heater core. The vent temp almost immediately dropped to 90 degrees, which was the temperature in my garage at the time. Then I drove around for 2 days, same problem.....only slightly cool air on day 1 and icy cold air on day 2.

The vehicle has been to 2 separate shops. Both shops discharged the system, checked for leaks and recharged the system. There were no leaks and the system was not low on freon. Of course, it worked fine while they had the vehicle. Can anybody help.... Please?

Do you have the air conditioner set to auto when the temperature change happens or on manual mode?
Does the above concern happen more frequently when the vehicle is idling and not so much when driving? The manufacture has release a technical service bulletin on the cooling fans not cooling sufficiently when idling for extended period of time such as sitting in traffic.


This guide can help

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

Please run down this guide and report back.

I always run the system in manual mode. However a few times I've moved both the fan speed switch and the vent selector switch to AUTO. Made no difference. I've also tried just the fan speed switch on AUTO and just the vent selector switch in AUTO. No change in vent temp when I do this.

The problem happens both at idle and at highway speeds. I've always noticed that the A/C isn't as cold at idle on this car. But this problem came on suddenly about 2 months ago while on a road trip. Was driving on the highway and it was 105 degrees outside. Didn't have a thermometer at that time but I assume the vent temp suddenly raised from ice cold to 80 degrees or so. Never touched the controls before the problem happened but I did start trying different settings after the problem started. Suddenly, when we were back in town and about 4 miles from home, it started blowing ice cold air again.

As a troubleshooting step, I've taken the car on the highway when it's acting up... it only very slightly lowers the vent temp (about 4 degrees or so).

Also, I've taken it on the highway when it's working fine. Then I notice a bit more of a drop in the vent temp compared to idle (about 10 degrees), but because its still nice and cold at idle, there's no complaints from the family.

Intermittent issues can be one of the worst diagnostic jobs given in my profession! Obviously the key here is get the a/c system to act up all the time so a proper diagnostic can happen. Unfortunately there are so many variables that can cause the above concern to happen. Is it a mechanical or electrical issue? A Ambient (out side the vehicle) temperature sensor signal can drop out (.-40Deg.) Causing the climate control module to shut down the climate control. A restriction in the refrigerant pipes could be causing a intermittent freeze up (internally). Broken temp blend door sticking open enough to allow hot air through. Temp blend door actuator internal gears worn causing door to stay open. Faulty wiring to a pressure sensor signal or any input or output wiring to control module
I would first try to pull any diagnostic fault codes from the climate control module to see if there are any code or history codes (the code will start with a B [or bxxxx] followed by four numbers). You'll need to get a hold of someone with a factory compatible scan tool to do this and access the module. If there are any codes this would certainly narrow down where to start testing.
As I mentioned before there is a TSB (reference number 01-01-39-004) which describes a loss in a/c cooling and the correction is to add a auxiliary cooling fan to increase air flow through condenser to assist in removing more heat.
Hope this helps you,TY

Thank you for replying and for the information, it's very much appreciated. Just a few more questions to help me further isolate the issue. You mentions a possible blend door issue. I think I isolated that as a potential issue by clamping the heater hose lines that feed the heater core. I then proved the clamps were working (cutting off ALL hot water to core) by turning the heat to full... there was no heat coming out of the vents. If the blend door was sticking, AND the AC compressor was running, could a faulty blend door still cause this problem given that the heater core's functionality was as removed from the system? Also, since the compressor is always running when the issue is present, I've been assuming a temperature sensor is not to blame. Is this a correct assumption? I think the only control over cooling that the system has is the blend door and the control (on/off only) of the compressor. Is that also a correct assumption? I mean, the climate control system processor can't regulate the orfice tube and can't regulated the amount of pressure supplied by the compressor, can it? When the AC is working well, the compressor cycles on and off regularly while driving around town and the vent temp stays in the low 40's.

Since the AC worked for years with no trouble, and suddenly started having issues, I'm not sure adding the extra fan across the condensor would be the problem. But I'm willing to try. I'll check on the service bulitine

Put gauges on the system today. Around 275 psi high side and 70 psi low side. AC was blowing pretty cold today.

Thank you again.

Air Conditioning problem
2000 Cadillac Escalade

The air conditioning for the driver's cabin does not get cool, yet the a/c for the backseat and rear cabin does get cool.

Sounds like a possible temp door actuator fault, or HVAC control module. Does it change temperature at all, or does it seem stuck in one position?

I checked today and discovered the Escalade already has that Aux fan installed in front of the condenser. It must have been done by a previous owner. I've always noticed the fan, it's fairly loud. I just never new it was something added later to the vehicle.... I always just assumed it came from the factory that way. Do you know how or where I can get a diagram or illustration of the entire AC system?

The temperature does not change; it never cools in the front, only in the backseat

I have access to about 26 images for the automatic air condition system. Most of them are wiring diagrams. Is there something specific your looking for?

If you have a voltmeter, and know how to use it, you can reference the following fault chart. Temperature Actuator Inoperative (FRONT) Step Action Value(s) Yes No 1 Has the HVAC Air Delivery System Check been performed? -- Go to Step 2 Go to HVAC Air Delivery System Check 2 Place the ignition switch in the RUN position. Disconnect the connector at the front temperature door motor. Connect DMM (volts) between the front temperature door motor connector, cavity 10, and ground. Is battery voltage present? -- Go to Step 4 Go to Step 3 3 Locate and repair the open in CKT 141 (BRN) between the IP fuse block and the front mode door motor. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? -- Go to HVAC Air Delivery System Check -- 4 Connect a DMM (continuity) between the front temperature door motor connector, cavity 7, and ground. Is continuity present? -- Go to Step 6 Go to Step 5 5 Locate and repair the open in CKT 150 (BLK) between the front temperature door motor and splice S244. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? -- Go to HVAC Air Delivery System Check -- 6 Place the ignition switch in the RUN position. Place the blower switch on the HVAC control module in the LO position. Make sure that the front blower motor is operating. Connect a DMM (volts) from the front temperature door motor connector, cavity 8, to ground. Adjust the position of the temperature control dial while observing the DMM response. Is the DMM response a smooth, variable voltage? -- Go to Step 9 Go to Step 7 7 Disconnect connector C3 at the HVAC control module. Connect a DMM (volts) between pin 8 of the HVAC control module, and ground. Adjust the position of the temperature control dial while observing the DMM response. Is the DMM response a smooth, variable voltage? -- Go to Step 8 Go to Step 10 8 Locate and repair the open or cause of resistance in CKT 733 (LT BLU) between the HVAC control module and the front temperature door motor. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? -- Go to HVAC Air Delivery System Check -- 9 Replace the front temperature door motor. Refer to Temperature Actuator Replacement . Is the repair complete? -- Go to HVAC Air Delivery System Check -- 10 Replace the HVAC control module. Refer to Control Assembly Replacement . Is the repair complete? -- Go to HVAC Air Delivery System Check I am not sure if the temperature actuator can be accessed in situ, for replacement it shows partial removal of the instrument panel. Here is a view.

(1) Blower Resistor (2) Blower Motor (3) Blower Motor Connectors (4) C230 (5) C203 (6) C204 (7) Temperature Door Motor (8) HVAC Plenium (9) Mode Door Motor (10) HVAC Wiring Harness (11) Blower Motor Relay, High The HVAC control module is the same as the control panel.

Your problem might not be any of those. I had the same type of problem.. My escalade has the digital settings for the AC heat, speed, etc. If yours is a digital type, there is a blower and a blower relay.... The blower relay can cause lack of heat, cool air, etc.... I changed my blower and relay last summer, no problems since.. The relay is up under the passenger side under the cover along with the blower.. Easy to change. I recommend YOUTUBE for the proper way to take stuff apart!

Blower is about $100 at Advanced auto and the blower relay is a little more.. The relay isnt going to look like your old one... Dont worry about it, follow the instructions, you might have to solder a wire yourself.... walmart has soldering guns with solder for ten bucks...

Thanks for that info. My escalade does not have the digital controls, just the regular knobs. Just a quick question.... Did your blower stop working? I mean did you have no air blowing from the vents? If your blower still worked...you may be on to something that I need to look at.

This is such a frustrating problem. Since there's so many issues with the blend doors on the Escalades and Tahoe's, almost everybody jumps straight to that as the problem with my Escalade. But, in my case, it's absolutely not the problem.

The fan/blower works perfect. The air out of the vents It gets hot when I move the knob to red and, 90% of the time, it gets ice cold when I move the knob to blue. But the 10% of the time that it doesn't work is miserable. I mean, it's not blowing hot air, it just blows ever-so-slightly cooled air. Probably like 85* or so. Of course when it's 110 degrees outside slightly cooled air from the vents is not going to do much.

I think the problem may be related to something in rear AC/heater area. I assume with this split system, having two expansion valves and evaporators but only one compressor, if one expansion valve acts up then the entire system pressure could be affected. So I vacuumed down and recharged the system using this guide and it fixed the problem.

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Please run down this guide to fix it.