1998 V70 XC Climate control no blower fan

Chef Rhody · Post by **Chef Rhody** » 21 Apr 2014, 20:29

So I am stumped.
My blower fan stopped the other day. I have looked at the ECC, resistor pack and the fan itself.
Today I got a used fan at the yard. Tested it with no resistance at the counter and it spun right up.
Went home, put it in, and........................it didnt work. So I started looking at the resistor pack. Went back to the yard, Got a resistor pack and nervously put that in. ......................didnt work.
Figured it had to be the ECC unit. Swapped the one from my wifes s70,...............hers works in hers, mine works in hers,........neither work in mine. I have eliminated the ECC from the equation. Double checked the fan worried that i had fried it at the junk yard. Hooked it straight to the battery (again, no resistance). Spun up good and fast. Now im certainly assuming that the fan is good. Only thing left is the used resistor pack I got at the junk yard. So I unplugged the one in my wifes car and plug in the one I got. Her system worked fine either way. Worked like a champ. Now Im ready to scream. Unplugged the fan in the s70 and tested for current. Did the same thing in the problem car to compare. The fan in my car is getting juice and looks to be the same as in my wifes car. It cycles through the same as if you were starting the car and I can adjust the current by moving the variable fan speed switch. The only thing left to do is to try my fan in her car but that seems like a waste of time as I can foresee the outcome. What am I missing? Whats left? As I said in the beginning, I am stumped. Any more than 3 components to this thing?
Oh most wise Ouija board of Volvo repair, please help!!!!!!!!!!!!

Post by **abscate** » 22 Apr 2014, 03:29

You have left off wires in your car out of your troubleshooting. Start at fuse box, check fuses, and all wires and connectors in between. Every one.

Chef Rhody · Post by **Chef Rhody** » 22 Apr 2014, 14:46

Thanks for your reply and input.
I dont think that's the case but I will double check.

However, just to make sure I understand the power chain, it goes like this correct??

1. Battery to ECC
2. ECC to resistor pack
3. Resistor pack to Blower

Post by **scot850** » 22 Apr 2014, 15:20

Have you checked the cabin sensor behind the dashboard? There is a little grill in the dash between the ECC and the first switch to the left of the ECC. To access it you have to remove the switch to the left of it and pull the ECC. It is fiddly to remove as you have to depress the 2 clips on the side and pull it re-wards. These things build up crud from the environment over time and seize. It is like a little fan unit. Take it out and carefully clean it and try again. Make sure it can spin. You may have to replace it.

I have also had problems with the fuses corroding so check they are clean.

Finally, I have had problems with the electrical portion of the ignition switch preventing power getting to the ECC.

Neil.