Blower or Resistor...Here We Go Again
 

2011 F-150 FX2 Luxury package. Dual, digital climate control.

I was driving along normally today. The outside temp was around 85, I had my dual zone climate controls set for 72 and 71. Everything was running normally.

All of a sudden, my blower stopped dead. No warning, no noise.

I checked the fuses and relay under the hood. All looked fine.

I pulled the blower and was ready to go pay FoMoCo for another one, when I decided to try one last test.

I hooked it up directly to the battery and it whirred to life, no problem at all.

BTW, the cage spins freely.

Resistance between the two pins on the blower itself is 0, if that helps anybody.

I checked for voltage at the 2 pin blower connector, and to my surprise FOUND voltage.

I ran through the different speeds and got some strange readings...

1 13.17V
2 13.08V
3. 12.94V
4 12.74V
5 12.57V
6 12.36V
7 13.68V

The first 6 seem pretty linear, but in the wrong direction. #7 makes sense that it should be full on juice.

I plugged the motor back in and it still did bupkus.

I'm assuming that there's voltage, but next to no amps. Not enough to drive the motor anyway.

Does this sound like a resistor?

The motor is a simple enough beast, I figure it must be fine.

Anybody seen this before?

I'm happy to pay to fix it, but I sure don't want to replace perfectly good parts.

More likely than not, a failed blower speed control module. Your DATC system doesn't use a resistor, the BSCM performs the equivalent function under the the command of the DATC module.

Is the blower speed control module the unit behind the glove box where the resistor normally sits? I understand that with the dual digital system with 7 speed blower there isn't a traditional resistor.

No EATC or DATC system uses a resistor module, they all use a BSC module. It's mounted in the same location in the plenum as the resistor in manual systems.

Thanks,
I've got one on order. I'll report back later in the week.

Fixed...

Correct diagnosis, faulty BSC module.

So much of the info online is for the older, non-electronic systems.

When my blower wasn't stuck on one speed, I had doubts about the problem.

Now, I can safely say that it was an easy 5 minute $65 fix.