2007 XC90 Blower Motor Issue

[mta]

Can anyone provide test details on the 4 conductor Blower Motor connector under the glove box. Need to test the blue & yellow wires at the motor to determine if the blower motor resistor pack is getting the proper signal from the switch on the dash.

Testing completed so far

Motor spins freely with 12VDC from battery
Replaced resistor pack
12VDC + and - at motor connector

thanks

[tailor]

I am not sure what prompted you to start the testing on the blower motor and what symptoms presented themselves to you to make you replace the resister only.

So, if the blower motor was behaving erratically, like never turning off and running the battery flat after the key was removed and car locked, ( normal operating procedure is that it runs a for about 10- 15 mins max after the car is locked to clear out any moisture) or you had no or little control, on the speed of the blower motor using the the controls of the climate control you likely had a faulty resistor.

The cause of the faulty resistor may be due to the excessive current draw of the existing blower motor. If you replaced the resistor without checking the the current draw first ,you may have taken out the new resistor due to the existing problem within the blower motor.

Typically the simultaneous replacement of the the resistor and the blower motor take place just in case the fault is with the blower motor……and anyone who has gone in and removed the dash to replace the resistor would want to replace both at the same time, as the time to do the job in this way, is about 8 hours. There is another way which is substantially quicker which is the method i assume you used to gain access to the blower motor.

Having said all of that here is a link to check the amp draw on a blower motor and also a youtube video ,albeit not on a volvo either.

http://am-us.delphi.com/news-spotlight/ ... or-testing


Below is a link to replacing the resistor removing the dash,
http://www.justanswer.com/volvo/1j0xh-2 ... istor.html