Heater Motor Resistor Question(s)
Platinum Member
Joined: 04-09-2006
Posts: 7,043
From: Vancouver, BC, Canada
Alvis. Alvis. Alvis. So. You didn't believe me and donbrew? 
All kidding aside. Most folks just replace the resistor. 99.9% of the time that's what it is if the blower only works on high.
Sorry, I don't have the specs on the that resistor. It's just considered a disposable part.
All kidding aside. Most folks just replace the resistor. 99.9% of the time that's what it is if the blower only works on high.
Sorry, I don't have the specs on the that resistor. It's just considered a disposable part.
New Member
Joined: 07-04-2013
Posts: 20
From: Michigan
To 843de and whopper:
No, it’s not rocket science, but science it is! I'm sure the electrical engineers would agree. Good comic!
To 843de:
Thanks for the diagnosis info. I measured the resistance between the four pins of my old HVAC blower motor resistor, and got either 0 ohms or infinite ohms (open circuit). That was sufficient evidence for me to run down to my local NAPA Auto Parts store and buy a resistor for $42.29 (part number BR367). Maybe I could have bought it online from the GM Parts Department web site for less, but I didn’t want to wait for it, and I did want to keep my local store in business.
The new resistor measured 0 ohms between all four pins. This was surprising to me, as I expected to find measurements of 2-10 ohms. I don’t get it (how a resistor can have 0 resistance), but I'll try to not lose sleep over it.
I had a tough time getting the resistor out of the HVAC housing. It is retained by two tabs that keep the resistor from falling straight down (no screws of the kind MrCatPC described on post "Water leak front passenger floor"). One tab is forward of the resistor to the driver’s side, and the other is rearward of the resistor to the passenger side. The location of the resistor makes it awkward to reach, and I didn’t even see the black tabs of the black housing in marginal lighting conditions. This is a bifocal-wearer’s nightmare! I was attempting to release the electrical connector from the resistor by unclipping the third tab, which is rearward of the resistor and on center, when I inadvertently dislodged the resistor from the HVAC housing. Fortunately, I didn’t break anything in the process.
Bottom line: if you measure infinite resistance (open circuit) between any of the four resistor pins, then it’s time for a new resistor.
firemangeorge and donbrew ("Water leak front passenger floor") GUESSED correctly!
No, it’s not rocket science, but science it is! I'm sure the electrical engineers would agree. Good comic!
To 843de:
Thanks for the diagnosis info. I measured the resistance between the four pins of my old HVAC blower motor resistor, and got either 0 ohms or infinite ohms (open circuit). That was sufficient evidence for me to run down to my local NAPA Auto Parts store and buy a resistor for $42.29 (part number BR367). Maybe I could have bought it online from the GM Parts Department web site for less, but I didn’t want to wait for it, and I did want to keep my local store in business.
The new resistor measured 0 ohms between all four pins. This was surprising to me, as I expected to find measurements of 2-10 ohms. I don’t get it (how a resistor can have 0 resistance), but I'll try to not lose sleep over it.
I had a tough time getting the resistor out of the HVAC housing. It is retained by two tabs that keep the resistor from falling straight down (no screws of the kind MrCatPC described on post "Water leak front passenger floor"). One tab is forward of the resistor to the driver’s side, and the other is rearward of the resistor to the passenger side. The location of the resistor makes it awkward to reach, and I didn’t even see the black tabs of the black housing in marginal lighting conditions. This is a bifocal-wearer’s nightmare! I was attempting to release the electrical connector from the resistor by unclipping the third tab, which is rearward of the resistor and on center, when I inadvertently dislodged the resistor from the HVAC housing. Fortunately, I didn’t break anything in the process.
Bottom line: if you measure infinite resistance (open circuit) between any of the four resistor pins, then it’s time for a new resistor.
firemangeorge and donbrew ("Water leak front passenger floor") GUESSED correctly!
Glad you got it diagnosed Alvis, and for not taking that cartoon the wrong way, sometimes a little levity gets mixed in with the technical stuff here.
New Member
Joined: 09-06-2010
Posts: 14
From: Ontario Canada
A hint on the resitor(coil)pack for the hhr blower motor.
I had the same issue for several months on mine and I finally looked at it yesterday. It only had the full speed or off. If you remove the resistor pack and scrape off the silicone over the lump on the board. That lump is a built in fuse/fusable link. You will find that there is no conductivity from one side to the other. it has either melted the solder across the link or the trace at the edge. I just scrapped the coating off the trace at either end and soldered 3 individual copper strands (probalby .005 inch diameter- just pulled out of a small copper stranded wire) across the fuse. I am not sure the fuse rating that would give me but it will melt before the trace does. If it does not and there is an overload it would just blow the fuse in the fuse panel anyway. Back up and working fine at no cost and just 15 minutes of time.
My 05 hhr 2.4 just hit 548,000 km (342,000 miles) last week. I did an engine swap at 485,000 last summer as I was hearing some timing chain noise and it was cheaper to drop in another motor that I picked up for only $300. AT 485,000 km it was still not burning any oil and ran perfectly and was only changed out as a precaution. It has been a great work car if you can get over the little things.
Dale
I had the same issue for several months on mine and I finally looked at it yesterday. It only had the full speed or off. If you remove the resistor pack and scrape off the silicone over the lump on the board. That lump is a built in fuse/fusable link. You will find that there is no conductivity from one side to the other. it has either melted the solder across the link or the trace at the edge. I just scrapped the coating off the trace at either end and soldered 3 individual copper strands (probalby .005 inch diameter- just pulled out of a small copper stranded wire) across the fuse. I am not sure the fuse rating that would give me but it will melt before the trace does. If it does not and there is an overload it would just blow the fuse in the fuse panel anyway. Back up and working fine at no cost and just 15 minutes of time.
My 05 hhr 2.4 just hit 548,000 km (342,000 miles) last week. I did an engine swap at 485,000 last summer as I was hearing some timing chain noise and it was cheaper to drop in another motor that I picked up for only $300. AT 485,000 km it was still not burning any oil and ran perfectly and was only changed out as a precaution. It has been a great work car if you can get over the little things.
Dale
