Topic: air/ht blower switch no air flow.
in Forum: C3 Electrical
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The rubber bullet thing is probably your ground. It goes to a spade connector fastened to one of your screws that mount the blower motor to the heater case. Needs to be hooked up.
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I don't know there, Mr. T....the "rubber bullet" sounds like the power wire connector to the blower. The ground usually only has a small rectangular plastic connector. The power feed to the blower usually has the larger, round "rubber" connector, so it will seal tightly to the blower motor terminal. Either way, if there is no power there with the key on, blower on High, then the fan ain't gunna werk.
Anyway....The relay under the hood, by the A/C box if the high speed relay...it ONLY powers the fan on High. The Low/Med/Med High blower power comes from the resistor in the air box. You can have a bad resistor, with no lo/med/med hi fan, but it should blow on High. If the relay is bad, but the resistor is good, it just wouldn't blow on high.
|UPDATED|8/10/2012 6:10:58 AM (AZT)|/UPDATED|
Anyway....The relay under the hood, by the A/C box if the high speed relay...it ONLY powers the fan on High. The Low/Med/Med High blower power comes from the resistor in the air box. You can have a bad resistor, with no lo/med/med hi fan, but it should blow on High. If the relay is bad, but the resistor is good, it just wouldn't blow on high.
|UPDATED|8/10/2012 6:10:58 AM (AZT)|/UPDATED|
Joel Adams
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Adams' Apple said:
I don't know there, Mr. T....the "rubber bullet" sounds like the power wire connector to the blower. The ground usually only has a small rectangular plastic connector. The power feed to the blower usually has the larger, round "rubber" connector, so it will seal tightly to the blower motor terminal. Either way, if there is no power there with the key on, blower on High, then the fan ain't gunna werk.
Anyway....The relay under the hood, by the A/C box if the high speed relay...it ONLY powers the fan on High. The Low/Med/Med High blower power comes from the resistor in the air box. You can have a bad resistor, with no lo/med/med hi fan, but it should blow on High. If the relay is bad, but the resistor is good, it just wouldn't blow on high.
I Stand corrected bro. By the great illustration the spade connector with the rubber is the power. I was thinkin it was going to a mounting screw. The resistor info is right on.
Sorry bout that. Good thing ya dint hook up the power wire to the ground.
I'll shut up now.
Anyway....The relay under the hood, by the A/C box if the high speed relay...it ONLY powers the fan on High. The Low/Med/Med High blower power comes from the resistor in the air box. You can have a bad resistor, with no lo/med/med hi fan, but it should blow on High. If the relay is bad, but the resistor is good, it just wouldn't blow on high.
I Stand corrected bro. By the great illustration the spade connector with the rubber is the power. I was thinkin it was going to a mounting screw. The resistor info is right on.
Sorry bout that. Good thing ya dint hook up the power wire to the ground.
I'll shut up now.
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Yeah...me too....
NOT! 
Sounds like a break in the wiring between the switch and the blower somewhere...
NOT! Sounds like a break in the wiring between the switch and the blower somewhere...
Joel Adams
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Ok I will try to keep short. Thanks for the photo's.
My front is different than yours. I have ac if that is the difference.What I am seeing is one wire with a plastic clip on the metal connector shown on your picture.And then I have the rubber connection which then goes to a radio resister and then connected to one screw for grounding and then its not connected to anything?
Trying to find the harness connection for this purple rubber tipped male connection, it has a rubber connectionat the blower and then a rubber connection after the resiter and then to the harness.Purple. and the plastic female connecter connected to the male metal connter sticking out of your photo. But no power.
I have power at the relay and it works took it apart it is working.I do not have power to the wires that connect to the resister going into the ac black box so can't test the resister, and testing any wires purple or the one connected to the front of the blower there is now power in any wire, so if I can get power to the resister maybe I can proceed, need to check where power comes from the harness to the resister and where I can trace that back to existing power so that is where I am!
From what I see the purple comes from the hi blo relay which is working and has power to blower motor but when testing the purple wire no power!
If the purple is power, on my blower the purple is connected to the blower screw and radio resister and then the rubber connection on the lower right of blower, so then what is the female connecting to the male metal connector on your photo,its not the grd and not the power????
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2 things
1. I hot wired from the relay wire to what I thought the pwr was purple and it ran so grd is good just have to find where the pwr is bad like I said no pwr at the plug that goes on resister plug in ac housing?
2 should there be power in the wire that goes to the fan switch? Is that why no power at the resister plug wire?
3. I need a simple diagram to tell me which ports go to what color vac hose on ac/ ht selector the right diagra are not working to what I select checked colors b it can't make sense of 1 to 5 ports no matter which way I looks at the switch don't seem to match picture and are not labeled 1 to 5 .
Done for the night.....
Thanks bb78
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I agree the relay has power to blower in high but the resiter not getting any juice,and no juice to switch. I MUST trace the wiring back to the fuse from that harness. It had been working but not recently, and the wire jungle by the fuse needs to get cleaned up.
Thanks again for the info
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