Hi everyone-
First post. My 2008 XC70 blower died earlier in the week and I couldn't get to until today (work/weather). I recently have been having water leaking from the upper part of the windshield. Vehicle does NOT have a sunroof. This became a real pain since the leak was causing humidity/condensation problems and the only way to see out the windshield was to keep two windows open (~30-40 degrees out). My first order is to fix the blower and then the leak.

The blower has NOT been squeaking. I at one point I thought there was a light smell of burning brake pads which could have been another vehicle or tractor trailer on the highway (or it could have been the 'blower resistor' letting out its magic smoke). I pulled the cowl up and I can spin the blower. It doesn't freewheel but it definitely spins without much resistance. I watched a youtube video on replacing the blower and do not relish the thought of doing so as a special tool is REQUIRED. The replacement blower in the video did not seem to spin any better than mine. I have blown blower resistors many times in other vehicles but this vehicle has a 'Blower Motor Regulator' - probably just a PWM (pulse width modulated) FET.

I wanted to check the fuse (duh - logical) before dropping ~$60 on the motor regulator but cannot seem to figure out how to get at the fuse. Attached is the the diagram of the fuse box under the hood and the fuse is # 11 (UNDER the 'A' part). I had removed the battery cable, 12V bus bar nut and disengaged four plastic clips but it still did not want to lift up. I figured it would be fuse, regulator, bad ground or blower.

So... does anyone have suggestions on isolating the issue? I could rip things apart but would appreciate thoughts on how to avoid wasting time/money. If I pull the regulator, is there always (fused) 12V present? And if anyone has thoughts on the leak as well but I will likely post separately after fixing the blower.

-Thanks-

 

I suspect my issue is the blower motor regulator. It looks like there is a four pin connector on the regulator - I would assume +12, Gnd, PWM input and PWM output to blower. The instructions indicate to remove the driver side console trim piece and the gas pedal which I did. This sucker is all the way up against the firewall. There were three nuts that held the gas pedal in but there was a formed steel bracket that the pedal assume attached to. What is unclear is whether this bracket is easily removable - there are two nuts above the gas pedal assembly but it might be part of a larger cradle bracket but it's hard to tell. I could not get a grasp on the regulator with the bracket in place. Has anyone replaced the regulator?

 

Before I did any of this repair, I would get a diagnosis from a shop with a scan tool that can read the HVAC system. If you can see the command to increase the voltage from the HVAC unit, it will probably give a code if the signal doesn't pass to the blower motor.

Most of my experience points to the blower motor itself. I have only ever changed the blower. Seems that the regulator is fine.

Another DIY test is to see if you can use a volt meter and probe the power side of the module checking to see if current is leaving the module in various voltage as you increase and decrease the fan speed manually.