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Heater fan problems 92 Olds.


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12-27-04, 12:13 PM   #1  
sparkync
Heater fan problems 92 Olds.

I have a 92 delta 98 olds, and having problems with the fan motor coming on. I can set the heater controls and call for heat. All of the functions, defrost, and the different air direction valves seem to be working, because I can hear the "shutter" open and close, but the fan only comes on randomly. I have checked voltage at the fan motor when the system is calling for heat, and there is no voltage there. When the motor does come of course there is voltage there. I have checked under the hood for a possible loose connection, and so far have found none. I think I have traced the wires to go through the fire wall into the dash section. I have went to the local parts store and looked at the schematic, and it looks like there is a high speed relay, and just a regular relay in the circuit, before it goes to the controls. Can anyone help me with the location of these, or possibly another sensor that I'm missing? Like I said the fan motor comes on, but with no regular sequence. Sort of comes on when it wants to, letting me know that possibly there is a loose connection or maybe a temperature switch that is hung up or something. Thanks for any help you can give...

 
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12-27-04, 02:45 PM   #2  
That car should have an automatic climate control system.The most common cause would be the blower motor control module followed by the programmer.The module is located in the blower case below the fuses/relay center under the hood back by the firewall.You will need to remove the center to access the module.It's basically an electronic blower motor resistor.That would be my bet.

 
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12-28-04, 02:07 PM   #3  
sparkync
fan box?

Thanks for the reply Davo. I'm having problems finding the fan box and resistor you referred me to. Is it visible under the fuse/relay center? I see 2 plug in connections there but can't see anything else unless it is in the fire wall. I started taking the fuse/relay center loose, but had trouble finding one of the screws that held it on. Thanks again for the help. Steve..

 
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12-28-04, 02:15 PM   #4  
If you found the fuse relay center try this first.Looking at the relays from the front of the car count over 4 from the left remove it and put the first one on the left in its place if that doen't work take the loose one removed from #4 position and put it in the #5 position and see if the bower works after each swap if it does you need a relay.Don't worry about putting the #1 position relay back during the test because its only for a/c clutch engagement.If this does not resolve the problem the blower control is under the relay center with 2 connectors attached.There are only 2 nuts holding it on one on each end.Keep us posted.

 
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12-28-04, 03:09 PM   #5  
sparkync
relays

Davo, so all the relays are the same type relays ? That is the #1, #4, and #5 especially? Thanks again, I'll have to try that maybe tomorrow or later. Got dark on me and it's cold out there . And also, the two connectors under the relay center, that goes to the fan box. Is the fan box actually recessed in the fire wall? Steve.....

 
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12-29-04, 03:56 AM   #6  
All of the relays are the same about 8 of them.The heater box is not recessed into the firewall but may appear to be so.

 
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12-30-04, 10:05 AM   #7  
sparkync
heater box

Davo, thanks for the information. I checked the relays like you said. They seem to be ok. The heater fan still didn't work. I took the heater box out. There were three screws. It looks like aluminum heat sinks. Is this the right thing? If it is, what might be next in the circuit, or how can I check this box. Thanks a lot for the help.. Steve

 
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12-30-04, 04:20 PM   #8  
You have the module it looks like a heat sink.You can check the red wire going to it for 12 volts.You can also check the purple wire between the blower and module for a short to ground.I would have to look at a diagram for more info as my brain only stores so much old info.I have to dump some of the old to store the newer stuff,kinda like a disk cleanup for my brain.Lol.

 
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01-02-05, 07:21 PM   #9  
sparkync
fan

Davo, I took everything apart, and didn't see any obvious problems. I believe while I had it out I tried the heater fan again. Still didn't work, then I tapped on the fan and it came on. I had checked the voltage on the fan before, and it didn't have voltage when it should have had. So I ruled out the fan. But anyway it started working, and is still working now. I don't know if there was a loose wire in one of the plugs on the heater box or not. I checked them when I had it out. Maybe there were two problems, a loose wire and also the motor. If it stops again I will check the motor out again. But anyway, thanks for all the help. It's good to know there are experienced people out there that are willing to help. God bless....

 
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