Blower Motor won't shut off

[sjptak]

It figures. We are in FL and were going to head north on Tuesday. My 1999 Chev 3500 Class C camper has been just fine. Yesterday, I was cleaning things inside and noticed no problems. Last night I went out there and the blower motor was running for no apparent reason. There was no key in the ignition, the AC/heat was in the off position and the fan switch was on low, but the fan was running on high speed. Has anyone had this problem before? Is there a solenoid or a relay that could stick and cause this? Where might that solenoid or relay be? It's time to head north!

[Gjac]

Thanks Mike I did not know what Plan B is. I thought it was part of Medicare. Where is it located in Milford?

[mike_brez]

sjptak wrote:

Gjac, I'll be heading just north of you. We will be staying in Seymour, CT. My daughter works there in Milford at Plan B.

Yummy my favorite burger joint in Milford. They also carry one of my favorite beers(Sea Dog Blueberry) and a nice selection of Whisky. That's it I'm headed to Plan B.

[sjptak]

PaulJ2, This problem is getting irritating now. It has graduated to an intermittent kind of thing now. When it happens, though, it comes on at high speed and no matter what I do with the dash controls, it won't go off until I unplug the blower motor itself.

Guess I'll have to hit the Chevy dealer tomorrow. If it's that relay, at least it looks to be an easy fix.

[PaulJ2]

The blower fan in a GM does indeed use a relay for it's high speed only. Used to be mounted on the air cond evaporator housing on the firewall, passenger side. Don't know about the later models now. Does sound like it is stuck.
Engine side of the firewall.

[Gjac]

Well if you have time stop and sat hi. Just PM me.

[sjptak]

I'm sorry, I guess I wasn't specific enough. I'm talking about the dash AC and heat blower motor. It's wierd, because it came on for absolutely no reason. Like I said, key was not in the ignition and the thing shouldn't be on. I guess I could just unplug the blower motor, but I'd like to have the AC on while heading north.

Gjac, I'll be heading just north of you. We will be staying in Seymour, CT. My daughter works there in Milford at Plan B.

[Gjac]

I have a 1996 Chevy 454 and the control for my fan is in the RH head. It is a plug that screws into the head and has a wire attached to the end. It is a thermo plug of some sort sensing the head temps and trigger the fan to go on when the head temps get to a certain temperature. I don't know if yours is set up the same or similar way but if after checking simple things like the switch position, try removing the wire to see if the fan goes off indicating a shorted out plug.

[Wheel_Estate]

check at thermostat .. many have a 'fan on' switch you may have bumped while cleaning. of course there is a chance the board died on the fnc, the fan comes on (to clear chamber) before ignition. If it was a no ingnition situation, i believe it would cycle on and off after several minites.