HVAC Blower Quit
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From: Insane Diego, California
HVAC Blower Quit
I get no response when I turn the front cabin blower speed control switch with the output control set to most positions, but the blower does work when in the defrost position. AC does not activate when the button is pushed or when the control is set to recirc.
Fuse checks OK.
Is this a relay problem?
If so, is there a similar relay on the board I can swap to test?
Other causes?
Thanks.
Fuse checks OK.
Is this a relay problem?
If so, is there a similar relay on the board I can swap to test?
Other causes?
Thanks.
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I get no response when I turn the front cabin blower speed control switch with the output control set to most positions, but the blower does work when in the defrost position. AC does not activate when the button is pushed or when the control is set to recirc.
Fuse checks OK.
Is this a relay problem?
If so, is there a similar relay on the board I can swap to test?
Other causes?
Thanks.
Fuse checks OK.
Is this a relay problem?
If so, is there a similar relay on the board I can swap to test?
Other causes?
Thanks.
Randy, also check Fuse 37 and the "Supply" relay at position X in the CE panel.
I have a detailed schematic for the '91 -on control head in process on the other screens. Just need to confirm that the head matches the schematic and it will be ready for prime time. Alan, if you could PM your e-mail address I can send a draft of it to you for a look. It's in autocad dwg format if you can use that, or I can PDF or DXF it for you. There are a couple things that puzzle me on this head-- It looks like the fresh-air blower relay seals itself in via a diode in the head, so that once control power from the Supply (X) relay via fuse 37 is in, it closes and powers its own coil until the X-relay drops out. Looks like there's no "OFF" position available on these newest control head versions like there is on most earlier versions. The car wiring to the connectors is the same though.
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Alan, if you could PM your e-mail address I can send a draft of it to you for a look. It's in autocad dwg format if you can use that, or I can PDF or DXF it for you. There are a couple things that puzzle me on this head-- It looks like the fresh-air blower relay seals itself in via a diode in the head, so that once control power from the Supply .... Looks like there's no "OFF" position available on these newest control head versions like there is on most earlier versions. The car wiring to the connectors is the same though.
Alan
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Relay is my 1st thought.....its an easy test...swap it with the horn or just jumper it....but since it works on defrost, it makes me think thats not it.....it sounds like the resistor pack to me.....does it work on "4" if it works on 4 but nothing else....then its the resistor (4 is the same as defrost)
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The DEF relay does not use the HVAC supply - it will work with no blower relay...
We already know the fan works in DEF only...
I think Randy knows what he needs to do next... we are waiting on him...
Alan
We already know the fan works in DEF only...
I think Randy knows what he needs to do next... we are waiting on him...
Alan
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