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Pontiac Grand Prix Heater blower relay switch



  • ejones86ejones86 Posts: 4
    I've read all these post about the ignition switch on older models of the grand prix dealing with the heat and defroster. Does this apply to the newer models as well? I have a 04
  • ejones86ejones86 Posts: 4
    what year is your car?
  • ejones86ejones86 Posts: 4
    its a 2004
  • biodan23biodan23 Posts: 1
    Since you replaced your thermostat it may be your water pump.
  • mwl76mwl76 Posts: 1
    I have had this problem too. My blower will quit and then restart the next day. This week it started and would not shut off even if the key was out. They only way to get it to stop is to remove a fuse. I have contacted GM. There is a recall. My car was not included. I reported it to NHSTA and you guys should do the same. My car started blowing smoke from the vents today. I have read the recall through an internet website. It will cause fires. GM has to fix this since it is a problem for all. The fire can not only damage your property but your health as well.
  • gmcustsvcgmcustsvc Posts: 4,252

    I would like to look further into your situation. Could you please email me your VIN? Also, include the user name from forum.

    Thank you,
    Caron, GM Customer Service
  • msconfusedmsconfused Posts: 2
    My car has been running very hot, hasn't over heated yet because I have shut it down. But what I'm also noticing is that the heat and air will be turned on all the way, and they wont blow out until I am driving at atleast 35 mph for a few minutes. I have been told it could possibly be the fan switch. Any info would help greatly!
  • gmcustsvcgmcustsvc Posts: 4,252

    Were you planning on having the vehicle diagnosed? Please keep us posted when the issue has been taken care of.

    Thank you,
    Caron, GM Customer Service
  • msconfusedmsconfused Posts: 2
    yes i have had it diagnosed, the code that was given to me is P0420.
    It all has a lot to do with the Catalytic Converter..... Which that has already been replaced and has nothing to do with the problem i am having now. The thermostat and radiator were also checked and those seem to be fine as well. I dont quite understand why these problems i am having would not register?
  • gmcustsvcgmcustsvc Posts: 4,252

    I would like to set up a case with GM Customer Assistance. In order to get the process started I will need your complete contact information (including full name, mailing address and phone number), VIN, current mileage and involved dealership sent to me in an email. Also, could you please provide a brief description of the problems you are experiencing?

    Thank you,
    Caron, GM Customer Service
  • My step fathers 02 Gran Prix has been doing this for a little over 6 months now. The dealer replaced the blower motor resistor did not fix the problem, Then they replaced the Blower motor did not fix the problem. We asked if it could be the ignition switch they told us no way . The lights now shut off when you turn the air down from #5 the Trip planner display turns on and off and the dealer said they have done all they can do. My step father cant keep paying the dealer ship $400.00 bucks every tine he takes it in and hope they can fix it.
  • mawilliz1mawilliz1 Posts: 7
    definitely the ignition switch. and stop going to the dealer! find a good honest mechanic on craigslist.
  • jroman2jroman2 Posts: 1
    I have an 02' Grand Prix and have had this same issue air will not come out a/c or heat unless I drive over 35+MPH , before that it would come out very light even on #5. Now my lights dont have problems neither does the console but a few months back my key would get stuck in the ignition and then the air started acting funny. Will this also be the ignition switch ? I dont have alot of money to spend and Diagnostics around my area are 100.00+ just to open the hood any help is greatly appreciated thank you.
  • The ignition switch can be purchased new or used! If you have a junkyard nearby it would be even cheaper. But you really have to be handy at taking apart your ignition. It's a bit tricky taking your "PASS KEY III" out, I took an ice pick to release it. There is a tiny hole in the collar, insert the pick and it will release it. I found out how to take everything else off by just asking around. The job should only take about an hour for even the not so mechanically inclined! Its only removing screws around the stearing column and disconnecting the wire harness. Once you get the pass key off, you are good to go! That solved all my problems with that issue. You should get away with doing the job for under $100! If you know somebody who could help you, maybe they'll do it for a 12-pack or something!
  • This is exactly what happened to me the other day. I went to shut off my 2005 Pontiac Grand Prix GTP and the fans didnt shut uff, i thought it odd since i had the keys of the ignition, but i remembered that sometimes the fan keep running, but this time it was the fans inside of the vehicle. went inside not knowing what to do. One hour later i cam eback out, my car was all fogged up and the fans were still running, now yesterday a lil bit smoke came out and now the fans dont even blow anything, at any setting!!! WTF whats wrong with my car..??
  • gmcustsvcgmcustsvc Posts: 4,252

    I apologize for the problems you are experiencing with your vehicle. Were you planning on having the vehicle diagnosed by a GM dealership? Please keep me posted.

    Thank you,
    Caron, GM Customer Service
  • Hey I noticed your post was from 2009. My car is doing the same thing. Did you ever figure out what the problem was?
  • i had the same problem, it ended up being the resister. its a hundred doller part available at any part store. its located under the dash on the passenger side. its a plug in item bolted in with two bolts
  • I went under and wiggled the wires and it been working since
  • That fix only works a few times. I replaced ours 3 times. Twice on my own. Unfortunately, I was stupid enough to have Meineke do me a favor and replace it the last time and they calked it into place. So, that when it blew again, I couldn't remove it. The real problem is that water leaks down through the hood cowl and shorts the system. Eventually, it works its way up to other areas of the electrical system.
  • Yup it was the blower motor "RESISTOR".. costed me $108 for the part and 50 bucks for someone qualified to put it on... no REGRETZ.. so happy i got it fixed.. WINTER is coming... HOPE THIS INFO HELPS OTHERS ;)
  • pam54pam54 Posts: 3
    I have a 2001 Grand Prix and sometimes my fan/auto lights/defroster/heated seat will not work all at the same time. Sometimes it will just kick on while I am driving. Sometimes it works just fine. I need to get this fixed soon, though, since winter is coming. Any ideas?

    Also, my gas gauge doesn't work anymore. It just fluctuates up and down.

    Any help would be appreciated. I need to do this as cheap as possible :)
  • Had the same problem. the hood cowl is the problem, here in minnesota the cowl buckles in the cold weather and water runs off the windshield under the cowl through the cabin filter on to the blower fan and resistor and rusts/shorts them out. My solution after I replaced the fan and resistor, I replaced the cabin filter one last time then used RTV black silicone caulk to seal the cowl to the windshield, haven't had a problem with water since.
  • Recently purchased a 2007 Grand Prix with similiar problems. Replaced blower motor because of excessive noise. Obviously water leaked onto it and probably started rusting up on the inside causing the bearing to squeek. Also have same problem with heater just cutting off. I have read other posts, just about all of them. The thing is mine doesnt cut off on just low speeds, but on all speeds. Was wondering if that still points to the blower motor resistor? Seen others saying it also could be ignition switch. I will take your advice and seal up the cowl with silicone for sure. Was wondering if anything I can do or should look for to be wrong also? Thank all of you'se for your advice and it is greatly appreciated. If you can please message back using my email address that way I can keep an eye out for a response. [email protected] Hope you had a good holiday weekend and Happy New Year to you and your family.
  • pam54pam54 Posts: 3
    I had someone I know look into it, and they said my main wires were corroded. They cleaned those off and I haven't had any problems since yet. Try looking at that first, maybe, before purchasing anything.
  • This is what I been thinking it was. You're the first to post anything about corroded wires.
  • My car is a 2002 grand prix i already change the blower resistor and it still doesnt work...i used to work only on level 5 while ago it stop working at all...please help whant can i do now..
  • Could be the motor itself. Mine would turn on but didn't have enough amps to run. Went and got one from wrecking yard and it worked fine. I know I have water that leaks in there when I go though the car wash and when it rains hard. If you have the same deal it might be worth checking.
  • I realize there water coming through...the motor look rusty....i probably change the motor if doesnt work I think would be the ignition. Switch
  • Do you know around how much is the blower motor??
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