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Front blower question

J

jrsavoie

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Rural Clifton, Illinois
I know the info is here but I haven't found it yet.
Isn't there a capacitor or something up behind the glove compartment that controls the fan.
1st we lost 3rd speed then we lost them all. Fuses are good.
I thought there was a part that goes out with this description. Any pictures here. It would probably be easier to serch for the threads if I knew the name of what I am looking for.
Part numbers? Going to get the parts tomorrow.
1996 Suburban
 
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3rd speed high is direct to the motor, behind the glove box is a red pigtail connector for the blower, well known fail that connector to overheat and make poor contact as it must be right at load capability, I'll have to dig around and see if i have the picture of it I had posted at the old site.

Sometimes you can restore operation by cleaning that connector best fix would be a hi power relay for the fan high speed, on my "to do" list as this intermittent connector is a problem on both my 6.5s
 
Yep definately check the 2 wire plug behind the glove box as I just went through this on my BURB as I was haiving issues with recirc not functioning. There is a blower motor resistor that mounts into the evap housing and it can fail and cause just one or the 1st 3 fan speeds to go out. High is controlled via the relay mounted on top of the evap housing behind the glove box.
 
in the airbox is a resistor (actually it's several all in the same unit) which is used to get diff fan speeds. Generally if one fails you usually have high speed (the resistors are used to slow it down). There is also a diode I believe which failed on mine but IIRC I still had high. It's kind of a pain to change. Probably more common is what TD said which I think is a problem with bad ground.
 
We had high then skipped a speed and had the lower speeds. Now we have nothing.
I replaced the heater/AC Cluster today. We had at least one connection that was visably lose - I attributed that to our recirc problem and knew all along that our fan was more than likely a completely different problem.
Thanks so far.
I forgot to note this is on the 96 Suburban
 
jrsavoie said:
We had high then skipped a speed and had the lower speeds. Now we have nothing.
I replaced the heater/AC Cluster today. We had at least one connection that was visably lose - I attributed that to our recirc problem and knew all along that our fan was more than likely a completely different problem.
Thanks so far.
I forgot to note this is on the 96 Suburban
Click to expand...

Since you say you also have a recirc problem, definately pull the glove box out and wiggle the 2 wire connector that hooks up to the HVAC box. I just went through this yesterday on my BURB, ended up being the ground pin was melted inside the plug. The blower motor ground is the ground for the whole evap housing's motors as well. You probably have a failed resistor and it caused high resistance and heated up the blower power plug.
 
The new heater/AC instrument cluster cured the recirc problem. The fan problem remains. I will do as instructed so far to the best of my abilities.
Thanks
I'll try to get some pictures as I go.
 
Back at this project. I pulled the resistor. It looked good to eye and had continuity every which way. I don't know that means it's good. I have a new resistor from Napa but it is to tall to get in.

How hard is the dash to get out. I'm sure there are detailed instructions with pictures here someplace. Anybody got a link?

There is one relay on top of the resistor. I am assuming it is the AC relay and has nothing to do with the fan. It is a Bosch and I am assuming it has been replaced at some point in time as it does not look OEM to me but it could be.

The AC works fine & I am assuming this relay has nothing to do with the fan problems.

It appears the problem plug was cut out many years ago and the wires spliced. They do not appear to be holding up very well. picture

Does anybody have a fine blower relay sketch like was posted for the lift pump relays?

My plan is to remove the dash and replace as many wires as possible with bigger wires.
If I can figure out the fan relay I will do that as well.
Thanks
Jeff
 

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Thanks
Found out today I have a bad fan motor.
12 volts is getting there but nothing is happening. Maybe I'd better run a direct ground to double check that.

The fan wasn't making any moise when it quit. Just up and quit all at once with no warning.

Got the resistor changed - that was probably my lost speed problem. I will run an extra ground tomorrow just to be sure the fan is grounded.
I suppose I could just check continuity from the fan to the ground bar.
 
The connector burns up as the aging blower motor starts to short out or drag/lock up due to bad bearings or brushes. All means high current draw. The connector is the first to burn up. Patching the wires with a shorting out motor will burn up the connectors again. And quickly at that.

So fix the connection again, replace the (bad) high current draw blower motor, and be done with it. A separate ground wire from the blower motor to a good ground really helps. In your case a locking up motor can burn out the safety fuses on the resistor pack. I doubt it as you lost high speed.

Your problem is the motor and those burnt up connections possibly including the OEM blower motor ground connection where that wire grounds.
 
Just from past experience, buy an OEM blower motor. Aftermarket ones suck! They're loud, unbalanced, made from inferior materials, etc. There is nothing as quiet as a genuine AC Delco motor.

Just my 2 cents worth, but I'll NEVER buy another aftermarket blower motor.
 
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