AC/Heat only blows on the High setting
AC/Heat only blows on the High setting
Anyone else with this problem please advise. My 91 Q only blows air after I manually turn up the speed to the last fan blade. On automatic it does it also but air only moves when the fan blades fill up on the readout(high). Do you guys think its a short in the fan circuit or something else. I went through the diagnostic in the service manual but the last 40 or so pages are missing out of the book. I'm pretty good aroung circuitry so let me know what I need to do. Any help is greatly appreciated. Thanks.:help
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
It is not a resistor it is a high power darlindgton transistor which receives a bias voltage from HVAC controller. Top speed is supplied by a relay which places 100% of battery voltage to the fan motor other times the voltage is supplied thru transistor.........transistor blows apart internally and is open circuit.
This happens when the fan motor gets old and starts drawing too much current..............replace the unit, if it keeps blowing change the fan motor also.
This happens when the fan motor gets old and starts drawing too much current..............replace the unit, if it keeps blowing change the fan motor also.