totallypaulie

I have a 1994 Chevy Cheyenne, two door with the 4.3L that belonged to my dad. It is in fantastic shape, except for when I turn off the ignition - the blower motor under the dash continues to run (more like a whirr), unless I press the OFF button on the AC controller panel first. As long as I remember to push the off button, no issues at all. (I should mention that I have no issues with the A/C or Heater. All fan speeds work fine when running)

Note: it's not pushing out any air through the vents when it does this. You can just hear the motor turning / whirring from behind the dash.

Yesterday, I was going to drive it to work after not driving it for a week or so and the battery was dead. It was an older battery, so it was time. However, when I put the new battery in, I could hear the motor from inside the cab turn on, so I knew that I had forgotten to physically turn it off the last time I had driven it.

I have only been able to find articles about this where the motor stays on all the time after the ignition is shut off and you have to remove the fuse to get it to stop - which is not what's happening here. Those articles say that it is probably the Resistor and/or the Relay.

Everything I read about faulty Resistors say that the motor will stay on always, one speed, or not at all. Nothing about staying running only if I don't actually push the OFF button.

Any thoughts or ideas on if this could be something different?

3,2,1 ... Go!

oilcanhenry

I know one thing. GM was the first vehicle manufacutuer to recognise that carbon monoixide could build up in a car (particularly back when carburetors were still used.).

So GM put vents in ther cars doors, as well as leavng the vent air to on the low/floor register to get rid of CO2. which could put a driver to sleep and cuase an accident.

Irish_alley

on my 94 the motor doesnt stay running once the key is turned off but the blender doors seam to return to a default location for a few seconds.

Terminal Frost

Chevy has a TSB about the wiring behind the radio causing issues to the HVAC control head. I experienced it on 2 of my Chevy's.
The dash mounting bracket behind the tape/cd player or relocated radio had pinched the wire harness running behind it.
Since this is a simple check/repair I would start here.

Then check the blower resistor.