Heater fan won't turn off

[HuskerWebhead]

It would appear that the "Off" position on my environmentals dial doesn't work. I can progress through all 4 levels of speed, but when I turn the vent position dial to OFF, the fan stays running. I can even cycle through the different speeds and it changes. If I leave it in the off position and turn the truck off then start it again, the fan is no longer running. It's just when I actually turn it on then attempt to turn it back off while the engine is still running.

Could this just be a dial issue, or is there a bigger problem?

Also, it would appear there is no difference in fan speed between 2 and 3. I'm not sure if there's supposed to be a huge difference or not, but I'm not feeling any change.

Thanks!!

 

[BigRondo]

Welcome aboard!!

I will send some good info from my shop manuals when I get home tonight.

 

[HuskerWebhead]

Thanks, I appreciate it. After doing more research I'm guessing the speed issue is the Blower Motor Resistor. Would the "Off" setting also be effected by the BMR, or is there another problem I'm going to have to tackle for that guy?

 

[BigRondo]

Sorry, I forgot about this thread. I'll check my manuals tonight.

 

[BigRondo]

Once again i apologize for forgetting about this thread.

I will try my best to get some info to you this weekend.

 

[BigRondo]

When I bought my Ex there was no change in speed between 3&4. I replaced the fan switch and this fixed it.

Since you said you are having the same issue between speed 2&3, I'm leaning toward a faulty switch.

If you let me know whether you have manual or automatic climate control, I can send troubleshooting steps from my shop manuals.

 

[HuskerWebhead]

When I bought my Ex there was no change in speed between 3&4. I replaced the fan switch and this fixed it.

Since you said you are having the same issue between speed 2&3, I'm leaning toward a faulty switch.

If you let me know whether you have manual or automatic climate control, I can send troubleshooting steps from my shop manuals.

Thanks for looking into this. I have manual climate control.

 

[Stuart chase BAJA 1]

Sorry, I forgot about this thread. I'll check my manuals tonight.

Hello all blower motor blues guy's. I had same issue to various degrees, replaced resister, noticed it had been done once before./ They left the lower screw out. popped top on relay ,contacts ok. Last resort was replace the on, off speed control switch. Replace that only to discover the problem for all the variable's was the external thumb switch. The plastic portion needed to grab the shaft was cracked and was slipping EVERYTHING OK. Best test is remove thumb switch and use a long nose to select speeds and off-on.

 

[J_C]

^ Welcome to the forum! Wouldn't having the problem that it was the back of the speed select knob itself, cracked, be noticeable because you no longer feel detents when changing to every speed position (and off) ?

It is curious that this topic's original posted problem did not come to a conclusion. With manual HVAC rather than automatic, it shouldn't (AFAIK) matter whether the vehicle was shut off and turned back on, or the fan control was turned off while still running. I mean the only way the fan keeps running is if the manual, selection switch for Max/Norm/Floor/Defrost/etc is set to off, but still conducting due to an internal short or wiring short.

The only other explanation I can come up with is that it wasn't manual but rather auto EATC controlled?