Thread: Stumped. Blower motor works on speed 5 *UPDATED*

Hi all-new here. Looked at some of your older posts-saw the same problem I have. 98 Grand prix--no blower speed on 1.2.3.4--high speed ok. Replaced resisitor--hooked up new one but did not install all the way--did not fix problem--different motor did not fix problem. When you turn the ign. on headlight will come on--I am presumeing auto headlight system because taillights come on. When you go to speed 1-no problem, speeds2,3,4 will turn off the headlights and turn off the A/C compressor--go to high speed and light come back on, blower works and so does the A/C. Any help would be greatl;y appreciated. Thanks

sounds like the resistor or the switch. remember, just cuz a parts new doesnt mean its good, especially with electronics

edit: after reading it completely, i guess i have no idea what would cause that to interfere with your headlights...

X2 as stated directly above me....that is where I would start.......I dont know.....find a priest and perform exorcism.

Might be your ignition switch they will screw with all sorts of stuff when they go bad.

After looking around on google I may have found the answer.


quoted from a post I found.

"
Sounds like the problem is with the ignition switch harness Part # 26068757 When your fan starts working intermittently on speeds 1-4, and eventually only works on the highest speed, this is the part that needs to be replaced. Goes from the steering column down to a large terminal block. Its almost 2 feet long and looks like a huge wire harness with big black connectors on each end.

Here is what ive found.

Once and for all I figured out the real reason behind the DRL-DIC-Fan problem. From what Ive read at clubGP it got me looking in the right area, the ignition switch. So first a big THANKS goes to everyone who said that harness fixed their problem.

All of these things get power through the ignition switch, specifically the RUN terminal (when the key is in the 'RUN'position), which is an orange wire on the bottom of the switch. When the problem was occurring I was getting fluctuating voltage on the RUN terminal (measured with a multimeter), jumping anywhere from .5 to 10, but usually hanging around 1 or less. When it was working properly the voltage read normal battery voltage, 14 or so. When the problem was occurring and I jumped that terminal to an always hot terminal everything came on and worked perfectly. So great, it's something in the switch.

Being the curious type I took the switch apart, figuring at worst I'd have to buy a new one... Would you believe the problem is carbon buildup a little larger in size than a pinhead? It's actually kind of nifty how they made this switch. When you turn the ignition key it turns a spring loaded plastic shaft in the switch. On this shaft are 6 lobes sort of like a camshaft, though not as tall. Each lobe has a rocker-shaped piece of metal spring loaded to rest on the lobe. As the shaft is turned when you turn the key it causes the various rockers to move out due to the lobes and make connections with terminals laid out by either side of the shaft. So, turn the key to RUN and the shaft turns moving the rocker out to make connection with the RUN terminal.

The beauty of this mechanism is how it can turn on or off certain terminals depending on how far the key is turned. An example of this is when you turn the key from RUN to START. The lights and fan go off because the RUN rocker is coming back down off the other side of the lobe as the START rocker goes up and makes its connection to send voltage to the starter relay.

It is this on-off-on action of the RUN rocker every time you start the car that I believe causes the problem. At the point where the rocker makes the connection to the terminal some arcing is taking place due to the volts and amps being drawn, causing a carbon buildup at that point. The more carbon that gets built up the worse the connection gets. Since the fan draws its voltage through this terminal more arcing is taking place if the fan is running when you turn the key. As a result there is more carbon buildup as compared to the other rockers that had very little or none at all since they do not have such high voltage/high amp devices to feed. I cleaned off the carbon with a soft wire brush and juggled around the rockers so the relatively 'unused'ones found themselves switched with the 'overused'ones.

I have not had a problem since then. Since the fan is probably the biggest contributor to the arcing and resultant buildup I am making a point of it to have the fan off when I turn the car on or off. This should help keep this problem from coming back for a great while longer.

~Larry~
"



Guess I am ordering up a new switch.. Anyone have a FSM for these cars in PDF format?

Thanks in advance.

not in PDF format, but i did just get my moms old scanner, which is working perfectly for me....
let me see how much free time i get today, maybe this could get moved to the "how to" section afterwards

edit: well im not finding **** under "ignition switch" in the index or anywhere, i love these books but they can be a serious pain in the ass....

ok, well, i have the service manuals, but cant find a damn thing related to the "ignition switch" if you have any suggestions for me to try searching for, let me know, but as of right now, i cant find it

Well replaced the ***ignition switch harness*** and all is good to go! It's not really that bad of a job, just for two little torx's you need a E-4! Other than that it's pretty straight forward took me about an hour to do the job after I got the E-4 *TORX* but.