Started the car today and the blower went to full speed and will not ramp down or even turn off! I press the economy mode and the A/C compressor shuts off but the blower remains on high. Even runs with the zero “0” off push button pressed. What do I check?
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Blower runs in High until key is off.
- Thread starter Phoenix127
- Start date
Most likely either a failed HVAC pushbutton control unit (which sends the speed signal to the blower regulator), or a failed regulator that is stuck on high speed. You'll need to be handy with a VOM to test, need to measure control voltage at the regulator signal wire. From memory it's something like 1v=low speed, 6v=high speed... if those values are correct with low button and high button pressed respectively, the regulator may have died.
FWIW, these measurements came from a known good system.Most likely either a failed HVAC pushbutton control unit (which sends the speed signal to the blower regulator), or a failed regulator that is stuck on high speed. You'll need to be handy with a VOM to test, need to measure control voltage at the regulator signal wire. From memory it's something like 1v=low speed, 6v=high speed... if those values are correct with low button and high button pressed respectively, the regulator may have died.
Post in thread 'Another Bad Blower Regulator? [Solved: Bad Ignition Switch]'
Another Bad Blower Regulator? [Solved: Bad Ignition Switch] | Heating and Cooling (Interior HVAC systems)
Good news! It was the blower regulator. Parts received and repair commencing.
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