Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Pontiac Bonneville Heating/Cooling Problems



  • bahappebahappe Posts: 5
    This is a 2000 Bonneville SSE type of car with dual controls.
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    edited August 2010
    The mode dooor should be operating both sides. It changes the direction of the air flow for both sides. You've got air coming from the dash vents on both sides.

    So your problem is the Air Mix door. I'd take the actuator off and see if the door moves correctly and when it moves if the AC air comes out cold or hot depending on the extreme of movement you put it at.


    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • bahappebahappe Posts: 5
    Thats it!!! Do you know if there is an easier way to get to either one of those actuators without having to take the whole front in or dash off? Do you know if there are anyother actuators besides the ones on the drivers side? Where do I get the actual actuator and do you know approximately how much they may cost? Thanks you sooo much.
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    edited August 2010
    Actuator at is 124. plus a substantial shipping charge.

    advance autoparts:
    Dorman HVAC Heater Blend Door Actuator
    Part No. 604-106
    Controls A/C Blend Door; Air Inlet Door; w/Automatic AC Controls; Dorman - OE Solutions

    Notice it's a DORMAN part. They make lots of parts. They are the HELP rack of odd parts at Advance Auto Parts and other stores.

    The actuator on the driver side is the same for the dual or single control.

    I think you just work from below to remove. It has one screw??? that holds it in place. It's keyed to the axle by shape so it can't be put on wrong. Be sure the axle without the actuator in place operates and gives the air cold and warm as you move it.

    Be sure to diagnose carefully before buying a replacement. Nothing like buying a part that isn't the one causing the problem!!! I've been there.

    You might shop the part number on Amazon and EBay, but there's a reality of being able to pick it up at Advance Auto or elsewhere near home and possibly return it if necessary.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • bahappebahappe Posts: 5
    Thanks alot. I will get involved in on this weekend and will check back in to keep you posted. Thanks again for all of your help. I will keep you posted! Kindest Regards.
  • air5air5 Posts: 1
    Turned heat on this morning but cannot get climate control to stop the heat. Tried unplugging temp sensor with car off and on to no avail many times. I've usually got it to work before when it gets stuck on heat by unplugging sensor but not this time. Any suggestions?
  • I have a 05 Pontiac Bonneville and on yesterday the heat would not blow from the vents all of sudden. When I switch everything on I can hear it turn on but no air comes out. If I keep it on (time ranges) it eventually begins to blow air. My pops told me it could be the heater blower motor. If so, where do I locate it on this particular model/year :confuse: . I would like to purchase a new one and replace ASAP. Do anyone have any suggestions?

  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    edited November 2010
    You can turn on the blower speed and key to test. If the blower fan doesn't start blowing, tap your foot up against the bottom of the heater case on the passenger side of the hump. If the fan motor makes contact, most likely it's a failed blower motor. But there are a few people who find the contacts on the connector to the blower motor will be overheated and burned causing contact trouble. will have a good price on most items even considering shipping. They have a 5% discount number for the where did you hear about us box: 43368333566713

    I found Autozones in this area stocked the blower motor. I had to go to one across town to find a store that hadn't sold their stock unit. Other box stores all expected to just order when someone wanted one. I believe it was $139 for the fan. Three screws and a rubber cooler tube are all that are needed to R & R after you take off the hush panel under the dash.

    Look at the connector first for damage.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • i have same yr car and same thing hppened we had to cut the power to the inside consul and splic a line with a toggle switch to get it to work
  • hey could u plz tell me where is the outdoor temp sensor is located?
  • since i changed my battery there is no heating , only cold air is coming out
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    The outdoor temp sensor is on the vertical metal bracket that is in front of the radiator--it probably holds the hood latch. It's a sensor about the size of your thumb with electrical wires going to it. Be sure you don't mess with anything with yellow wires; those are the airbag sensors for crash.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    edited January 2011

    Try disconnecting the plug at the sensor and see if the system goes to a default value for outside temp.

    If the car senses the outside is 90, it's not going to give you much heat inside.

    Sometimes the connectors get corroded. Try reconnecting it to get a good connection. They do go bad. About $13 at

    There is a remote possibility the electric actuator that moves the heat blend door inside the heater broke when you reconnected the battery. But get the outside sensor working right first before worrying about that.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • Open your hood and look down at the center of the radiator near the bottom if it.
  • thank you bro, but still not working, sensor is still flashing, when i turn the heat on, for about 30 seconds it works good but after that only cold air comes out. it happens most of the times, but some times i get perfect heating. do you have any idea?
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    edited January 2011
    Next step is take off the underdash panel on the passenger side. Locate the programmer box on the corner of the heater box. Look for the electric actuator on top with little wires going to the programmer box.

    Watch the rod on the actuator as the arm swings when you move the temp from cold to hot to cold. Leave some time for the computer to react.

    The movement should be steady. If it's jerky the gear on the actuator is slipping on the hub inside the actuator. Some people have removed the glovebox and put a coathanger through a hole in a brace on the dash on ceertain models of Bonneville to the rod sticking out of the heater box that connects to the actuator link. They just snap together from the rear. They use that to adjust the heat until they can get to taking out the actuator for replacement or repair. It has two small screws that hold it in. On Bonnevilles they are tighter to get to than in leSabres.

    If you can move the link with one finger by making the gear slip on the hub inside the actuator, that verifies what has happened.


    I made sure the gear was in a part of the movement range where the blue gear wouldn't hit the crack and glued mine to the hub with a little 5-minute epoxy.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • gbowiegbowie Posts: 1
    I have a 99 Bonneville. Every time i start the car the temp setting flashes for about 1-2 minutes. I then have to bring the temperature setting down to 60 degrees, wait a couple of minutes & then bring the setting up to 90 to get heat. This happens everytime I turn the car off. The dealer cleared the codes (1040 & 1052) & it worked for a week until i disconnected the battery. I had the dealer clear the code again but this time it didn't solve the problem. The car is warmed up. Any one have suggestions?
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    See post before yours. It's likely your problem is the electric actuator motor. the flashing may be because the unit can't operate the temp control properly or some cars sense a low coolant (freon) level because of the cold temps. But take a physical look at the movement of your actuator links.\

    Good luck.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • pooh4949pooh4949 Posts: 1
    Good Day All,
    My 1996 Bonneville SE with climate control will not divert the air to the main vents. The only way it will come out is at the defrost and floor. What is the problem?

    Many Thanks
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    edited June 2011
    Are you able to hear doors move inside the heater box when you change from defrost setting to floor and to floor/windshield? And when you switch the recirculate button on?

    You might run the motor and then turn it off; there should be vacuum stored in the tank behind the right front headlight under the fender and you can hear the doors move.

    If you do hear movement, then you probably have the collapsing nipple inside the soft plastic connector on the corner of the programmer box on the edge of the HVAC box under the dash. Here's how to replace it.

    I'm told the 7/16 inch vacuum line is the right size to connect the ends of the plastic vacuum lines. I used something else when I did mine. Plastic tubing such as for aquariums does not fit tightly enough.

    If no movement, you may have a vacuum line off, split open, dry rotted, etc. Or the vacuum bottle under the fender may be cracked and not storing vacuum.

    I believe your vacuum tube layout on the engine is like my 98. The 92-95 had a vacuum line to the firewall to the storage bottle and those kept getting disconnected when people put their arm in to do things with spark plugs on the back of the engine.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • Clean Evap core, replace Blower and resistor. All the settings work(from defrost to vents to floor)
  • phr04phr04 Posts: 1
    The instructions for replacing this motor seem to indicate that it can be reached by removing the instrument panel cluster. I have done that and am still a long way from even being able to see the actuator. It appears that the entire dash panel assembly, including the air ducts must be removed. Is this true, and can I find step-by-step instructions for doing this?

  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    edited October 2011
    > It appears that the entire dash panel assembly, including the air ducts must be removed.

    No. It can be done by removing the underdash hush panel (thin plastic) and taking off the glovebox door.

    If you want to email my email given in my profile (click on my user name at top of this post), I'll try to link you up with some help.

    The Bonneville has a different dash structure in that area than the leSabres. Yours is harder to get to.

    First, you need to verify that the electric actuator is not moving correctly, by looking through the hole in the brace behind the glovebox where you can see the rod that the actuator uses to move the door. If you find the actuator is bad, it can be removed by taking off two short screws--but they do it by feel since they're next to impossible to see.

    What happens is the actuators have a plastic gear inside that splits so it's not pressed against the hub and slips. The hub is what moves the actuator rod.

    I removed mine and glued the gear to the actuator. But mine is easier to replace if it breaks or slips again. So I decided I might not own the car by the time it comes loose from the plastic instant glue.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • ac82ac82 Posts: 1
    I am in the process of replacing the blend door actuator on my 98 Bonneville. I can not access anything behind the glove box so I removed the cover off the blend door / A/C coil box to get to the actuator motor...Now I can't get it to go back under the dash...It came out so I know it has to go back in! I am at my wit's end. I would appreciate any help!
  • I'am having problem removing the programmer. I have removed the cover under the programmer, and the glove box, and can't seem to get any futher. I see the tubes going into the box, but now I still can't remove it.
  • I have a 1998 sse Boniville the blower motor would quit intermeditley now it quit working. I check the motor by running wires from the battery and it works great. Controls inside the car show the blower on any speed but nothing i have checked all fuses I show about 9.5 volts in the wires going to the motor. I have digital controlls. is that enough voltage? I don't know where the blower motor control mod is? or if that is even the problem or if the voltage is to low. I do know that there are three computers that control that system. Any help would be great as it is the wifes ride and I'm in the dog house untill i get it fixed.
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    edited March 2012


    The location is where shown. Follow the wires from the blower motor up. The relay center above the blower control module is held by two screws. Remove those and it can be pushed upward with slack on the wires and give some room to get the BCM out of the airbox.

    The module is electronic. They will show voltage but no current. If the blower runs when connected directly to the battery on a fused line and with a ground, then you're probably needing the BCM for roughly $100? Available at and other local box stores.

    If you do not have the digital speed control on the blower, then the same location would have a resistor set that gives three speeds.

    The only other possible problem is burnt contacts on the connections due to high heat. So take a look.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • Trying to figure out what could possibly be wrong with my wifes car. When the A/C is on the cool air blows out from the floor vents just fine ( I think ). When you push the button to go to the vents on the dash board, the air coming out of the vents on the passenger side comes out cool but on the driver side there is a noticeable (hotter) difference. Does anyone have any idea what could be causing this. I thought it might be the blend door actuator, but the air itself is being diverted correctly, the only problem is the temperature of the air on the drivers side vents on the dash when it is on A/C. Any help that anyone can provide will help out immeasurably.
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 21,399
    edited March 2012
    You are dealing with three separate electric actuators.
    One controls the direction of airflow for both systems, driver and passenger sides. That is not a problem since you can change the air flow path which is the same for both sides.

    One controls the air temperature blend door on the driver side.

    One controls the air temperature blend door for the passenger side.

    By removing the underdash plastic cover carefully, you can then watch the movement of each of these by the white center rotor on the electric actuator while you change the temperature demand on the dash with the key ON (I don't think the engine has to be running).

    I suspect you'll find the driver side is not moving all the way through the range of motion.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • First thank you for all the great information.. I lost my highest fan speed and I looked at the illustration above but I cant tell if I replace the fan motor from under the hood or under the dash, can you please point me in the right direction on what I need to do Thanks WM
Sign In or Register to comment.