HVAC blower motor
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Vegas, Baby!
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HVAC blower motor
It's gotten hot here in Vegas the last couple of weeks. My A/C in my 89 has been working very well till yesterday afternoon. Temp was around 112 to 115, while heading over to the club for supper. About 30 minutes into the trip, stop and go traffic my front blower stopped, and would not run at any speed. I switched to the rear unit and it ran without any problems, but it couldn't keep the cabin temp comfortable, just to small a unit. Figured it was a fuse, and I'd change it when I got back home.
I was at the Leatherneck for about 4 hours, when I started the car the blower came back on, and half way home it conked out again. Could this be the blower resistor pack going south, or a relay overheating?
Thanks
I was at the Leatherneck for about 4 hours, when I started the car the blower came back on, and half way home it conked out again. Could this be the blower resistor pack going south, or a relay overheating?
Thanks
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From: Double Oak, TX
More than likely the resistor pack - in stock and $132
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
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From: Phoenix AZ
This is the late model version of 'Magic Bower Syndrome' - on early model cars: when the blower resistor overheats it goes to full speed mode (since it gets cooled by the airflow and full speed mode does not dissipate any power in the resistor pack).
e.g. the thermal switch is normally open and sits in parallel to the blower resistor pack.
Later model resistor pack versions swapped to a mode where the resistor pack simply cuts off the blower if it overheats.
e.g. the thermal switch is normally closed and sits in series with the blower resistor pack.
In the latter case max blower speed (4) and DEF should still bring on the blower at full speed.
Alan
NB The last models 94-95 GTS have no thermal switch, they also have only 4 speeds (3 resistors Vs. 4 for all others) with a true off in speed 0 (all others run at slow speed in 0). The blower resistor is also not mounted in the air intake plenum for these models.
e.g. the thermal switch is normally open and sits in parallel to the blower resistor pack.
Later model resistor pack versions swapped to a mode where the resistor pack simply cuts off the blower if it overheats.
e.g. the thermal switch is normally closed and sits in series with the blower resistor pack.
In the latter case max blower speed (4) and DEF should still bring on the blower at full speed.
Alan
NB The last models 94-95 GTS have no thermal switch, they also have only 4 speeds (3 resistors Vs. 4 for all others) with a true off in speed 0 (all others run at slow speed in 0). The blower resistor is also not mounted in the air intake plenum for these models.
