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Pontiac Grand Prix Heater blower relay switch



  • gdainesgdaines Posts: 2
    I have 2001 grand prix, similar problem to many with heater/ ac blower, rear defrost, and daytime running light working sporadically. I understand that all three function through a common relay switch (not referring to the blower resistor pack). Does anyone know where this relay switch is located?
  • gdainesgdaines Posts: 2
    Thanks for your help, good info.
  • rrogan1rrogan1 Posts: 1
    Hey, I've looked through this thread and noticed a few problems I have. I'm just not sure if I have a problem with the ignition switch or not because I don't have many of the problems. My blower motor only turns on at 5, and I just recently replaced the blower motor resistor because it was damaged by water from the A/C I believe. Now the new resistor is acting up, and I'm thinking could be due to the ignition wires. The only thing is that I don't have problems with my running lights, or rear defroster. The clock does show weird digits sometimes though, and the rear speakers turn on and off randomly too. Do you think it's the ignition wires, or could it just be that the resistor got damaged by water again. I haven't seen any puddles in the passenger side like I did before when the old resistor died. Thanks for any help.
  • craig32craig32 Posts: 30
    This may not solve your problem, but it may help get you on your way:

    My blower gradually started failing on each of the fan settings (last1 being #5, then failed on that, too).

    I still have my blower not working on my '02 grand prix, and i've done the following:
    put 12 volts directly to the blower equaled it was good!

    I then replaced the resistor (twice, to make sure), and it was also good.

    ****I then thought to ck the voltage after the resistor, going to the blower, and it read (trying it at ALL the fan settings) 6.5, to about 7 volts (=not enough for the blower to work!!).

    A mechanic i spoke with said that it sounded like the voltage was 'shorting' somewhere, and that i should ck the voltage at the fuse panel.

    He said if the fuse was getting 12 volts, then the short was 'after' the fuse panel (either between the switch & the panel, or the switch itself).

    I mentioned this thing about others having the problem behind the steering wheel (eg, the wiring, ) & he said anything is possible.

    Keep in mind, if it's in the ignition wiring, you'll have to take a lot of things apart (if it's the switch, even more!).

    Consider also, the dex-cool/gasket problems (i'm selling the car!!)

    *****Has anyone else taking readings & gotten low voltage after the resistor (going into the blower)???

    What caused it????
  • Had the same problem as most above on my '02 Pontiac Grand Prix GTP - blower not working, puddle in passenger side, everything else works fine. Only had to replace the blower ($90) not the resistor. Replacement not too bad with the right type and length of tools.
  • On my 2003 Grand Prix, first my radio reception goes out, can only get very close stations, the cd player sounds unbalanced then won't eject cd, finally does eject it one day then I can hear it continually working with no cd.That stopped now. After that my AC started hesitating before coming on, now it will only come on if it is turned on before starting car, any attempt to adjust it, and it turns off. Or... it doesn't come on at all when started, but will come on much later on it's own...or not.
    What could the matter be?
  • I just finished replacing the heat resistor module on my 1999 Pontiac Grand Prix that everyone states is needed to get fan speed 1-4 working. My car will work on five only. Well it still only works on five only. I tested the switch by using a jump wire from hot to make sure 1-4 are working and the switch is good because it still does not work. Now I have been told that it is possibly a blower motor control module. This module is on drivers side, by left leg, near outer panel of door. It is also a very expensive part. It seems the switch relays are small, and they go through this module to a set of stronger relays then on to the heat resister module. Has anyone ever heard of this going bad and are there any after market ones that are available.
    The next issue, is still with the blower. With the lights set to come on automatically like most cars are today, if the switch is off, the lights will come on. The second that you turn the blower switch to 1-4 the lights will go off, and only come back on by going to off or 5. Somehow this is all tied together. Any ideas from the experts on this panel. Thanks.
  • Hi I'm an master auto tech and I recently had this same problem on a 2002 GP the trouble lies in your " Ignition Switch " the orange wire that comes from it feeds the HVAC, Day Time Running Light, Rear Defogger and some others. So I hope this helps you and others with this problem. P.S. I would personally get one from the dealer might cost a few bucks more but worth the piece of mind.
  • The blower motor on my wife's 2000Grand Prix GTP simply stopped working one morning. Does anyone know if there is both the Blower Motor Control Module and the Resistor pack when the car is equipped with climate control? The on-line and Chiltons manuals I have do not identify what makes up the components of the Climate control system. I can't even find pictures or locations of the resistor pack (if used) or the BMCM. Anyone have any advice re: location and serviceability of these 2 components?
  • Hi, I have a 2002 Grand Prix GTP. Fan speed 1 through 4 don't work. Fan speed 5 works well. No problems with Day time running lights, rear window defogger, etc. Can you confirm that by replacing the ignition switch, I'll have the 4 speeds back? Is there a way to check if it's indeed the ignition switch that's causing the issue?
  • Look at the dic/hvac fuze behind the glove box cover. If it has less the 12 volts on the fuze with the heater blower motor in a middle position and the head light switch off, with engine running it is probably the ignition switch. If the heater blower runs set to max (5), the blower motor is good. If the blower fails to run on some settings other than 5 but runs on others, and you have 12 volts or better on the dic/hvac fuze, it is probably the resistor pack, located behind the blower motor above the floor on the passenger side. If you pull the blower motor, oil the bearings, and check the drain hole is open (engine side). The dic/hvac 20 amp fuze is shared by many circuits, the day time run lights, seat heaters, rear window defogger, and the fancy style heater accessories, depending on the exact year of the car. All these are fed by the 60 amp ignition 2 fuze in the engine fuze block, then through the 20 amp dic/hvac fuze with the key switch in between. The DLR is located above the parking brake peddle but not much appears to go wrong with that but less than 12 volts feeding the DLR will not trigger the day time lights. Mitchell has a complete wiring diagram I got from the web for around 12 bucks, an actually has all the circuits in the set, something like 50 pages of complex diagrams! I found them here: The diagrams in the usual manuals from Checkers are worthless, as is who ever designed the heater resistor pack placement at GM for the Grand Prix. Hope this helps.
  • Does anyone know where the fan motor resistor is located in grand prix se, 2002
  • KAY65KAY65 Posts: 3
    I have a 2004 Pont GP. My blower will not shut off even when the engine is not running. It will only blow on #5. I have pulled every possible fuse in both electrical panels and nothing shuts it off. I took it to a mechanic and the only thing that he could do was to disconnect the blower all together. Now, I am without heat & window defroster which is a necessity. Please give me the magic CURE that's not going to cost an arm and a leg. Thanks in advance.
  • KAY65KAY65 Posts: 3
    I have a 2004 Pont GP. My blower will not shut off even when the engine is not running. It will only blow on #5. I have pulled every possible fuse in both electrical panels and nothing shuts it off. I took it to a mechanic and the only thing that he could do was to disconnect the blower all together. Now, I am without heat & window defroster which is a necessity. Please give me the magic CURE that's not going to cost an arm and a leg. Thanks in advance.
  • lberglberg Posts: 3
    1st the ignition switch would not go back to the off position but I'm able to stick a screwdriver up the hole under the good
    2nd gas gauge freaks out..up and down..have to watch my trip odometer
    3rd the radio digits go haywire the come back
    4th winter and I freeze windows up on inside
    5th blower doesn't work..managed to " unthaw " it and worked..sort of
    6th now it only works in the 5 position
    7th Sell this 2001 Gran Prix???? Kinda depressing
  • I am currantly experiencing the same condition with exact automobile and have come to learn the problem is called blower motor resistor. Thats what NAPA autoparts use for nomenclature. Others call it a module. Price ranges from 65.00 to 100.00 at dealerships. The fasteners used are metal rivots which does not replacement as easy as i had hoped since it's 15 degrees outside and i have no garage.

    hope this helps and you are able to enjoy the holidays.
  • Careful!

    Although, apparently, the 2 things that are the most common to go bad (eg., the blower motor itself, or the resistor, just outside the blower), many people went & bought the resistor, only to find they spent money for nothing, as this wasn't the cause.

    Don't install the new resistor,...just , carefully, plug it in, to see if this fixes things (that way, you can retiurn it for a refund, if it doesn't!).

    I haven't had air/heat for 2 years (but live where climate is bearable).

    And, same as most: fan speeds stopped working until only #5 setting would work,...but then, not even that!

    It should be asimple fix (anyone know how to test the body control module, without removing half the dash???

    There must be a way of feeding getting the blower to work, & still send power to work the neccessay vacuums, other necc systems for air/heat, without fixiing the ignition wiring (it's a BIG job!).
  • I have a 2004 grand prix gt.When I start the engine and turn the heat on the blower will only come on after about 10 minutes of driving.The blower works fine once it's running but if I shut the car and restart then I go through the same thing again.
  • I have a 2004 grand prix gt.When I start the engine and turn the heat on the blower will only come on after about 10 minutes of driving.The blower works fine once it's running but if I shut the car down and restart then I go through the same thing again.
  • torybtoryb Posts: 3
    im having a prob with my 2004 grand prix i saw you mention the the ignition switch wires .im hoping thats whats wrong with my car but it also over heats too and cant figure out why . we changed the radeaitor and water pump and the thermostat can you help
  • KAY65KAY65 Posts: 3
    I got tired of dealing with this problem so I took it to the dealership. They said that it is a common problem with the Pontiac Grand Prix. After inspection, it was determined that the Resistor shorted out the Blower Motor. Both part had to be replaced. The dealership cost of the Resistor Module $92.80 and the Motor $164.10. Labor $273.74.

    As for over heating... More sure that you are using GM Parts ONLY!!! Other brand parts for this car causes problems. Stay out of Advance & Auto Zone!!!

    Good Luck!
  • mkn1mkn1 Posts: 2
    OK... this morning I turned on the heater and it started out being normal then started reducing in speed. I then went to the different levels 2,3 4 and 5 with the same results. At level 5 it was blowing at level 1 speed and finally quit entirely. Is it the motor or relay or aliens.... 2003 Grand Prix GT, 162000 miles.....
    Thank you
  • mkn1mkn1 Posts: 2
    mkn1 continuation:
    In reading this forum further there are a few more symptoms;
    I no longer have to depress the brakes to shift into gear.
    There has been times that my radio display flickers.
    I can't get my ignition key out unless I physically release it by going under the steering column.
    Any help would be appreciated.....
  • so we know that the rain draining on the passenger floor could be the caused of the problems to the wiring and possible the blow motor had same issues except that when blower was working for me that 1 to 4 was working and the 5 wasn't on occasion, also don't know about my lights if they were woking when the blower motor was working I have one of my fog lights out but seems all my lights are working when the blower isn't as I took a look tonite tried various things but no blower tried turning over ignition playing with the wiggling the key lock to see if it was a short to see if blower would come on it didn't. It seems that had difference with other peoples problems which I may think it could be the blower. I checked all the hoses to see if was running hot seems all of them were also changed thermostat wasn't the problem checked fuses under hood they seem all ok not to sure about the relays also took a look at the blower itself looks like water all over it from rusty water marks from the rain and probable washing the vehicle. Cause everything is fine except the blower and also had the dimming and then ok on occasion within a split second or two so anybody have sugestion on that problem? a 1997 grand prix GTP model
  • az_98gtpaz_98gtp Posts: 3
    Hello there, I am having trouble with my 98 Grand Prix GTP heater/AC blower motor. To begin with, I was having trouble with only getting heat from the passenger side vents and cool air on drivers side as well as my blower motor was having extremely loud screeching noise coming from it. I still had all 5 motor speeds the best I can tell or remember.

    After hunting around for answers on the Internet at different web sites, I found this link saying to change the left/right side door actuator. After taking my actuator out and finding the gear was broken like shown at the link, and thought I had myself a quick fix and ran down to the local wrecking yard to get a good one.

    I replaced that and proceeded to fix the blower motor noise. I took the motor apart and cleaned and oiled the bearing on it and put it back together. After I plugged it back in, the blower motor would only turn on for a few seconds and then turn on for a few more seconds real soon there after. It does this every time I turn on the heater control and shut it back of again. I have tested 12v to the motor and it does run just fine.

    I proceeded to replace blower motor control module and still no luck getting the blower motor going. Also I do have heat in my seat, HUD works fine and no other noticeable problems besides the blower motor not coming on.
    Is there a way of resetting the system in any way at all?
    PLEASE help! Thanks!!!! :sick:
  • It appears a whole slew of problems can arise with a bad ignition switch. I recently bought a used 1999 Grand Prix and was told (when I bought it) that the key doesn't always come out of the ignition and the switch will need to be replaced. I got around it for a few months by manually removing the key. First the lights on the radio went, then the blower on the heater followed. All seemed to be going ok until yesterday when the car did nothing. It has no power at all, but the battery appears to be holding a charge. I can't even open the truck with the button in the glove box. Could these problems all be related to the ignition switch?
  • elfriedaelfrieda Posts: 3
    I am replying to myself, seems the ignition switch started shorting out the radio, cd player, etc. When I replaced that, The AC/ Heater/Blower all worked again but had to replace the Radio/CD.
  • juceejucee Posts: 1
    Hello I have a GP 98 and the ac is blowing but not at the level it's on it's blowing cool but at level 1 on 5! Also, it cuts off once the RPM starts going crazy! I just had the ing switch changed b/c the key wouldn't come out.
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