93 Volvo 850 - AC is fubar...help!?

clt850guy · Post by **clt850guy** » 07 Nov 2005, 15:33

Hey guys

I have a 93 Volvo 850 with Electronic climate control... it's FUBAR....

One day, while driving, burning electronics smell came out of the vents. Lights on dash start flashing. After that, AC stops working completely. Open up the dash and remove the fan, ballast resistor. Open ballast resistor and it shows no signs of damage on the circuit board (no blackened capacitors, resistors, etc). Take the fan and hook it up to the battery... cranks up fine. Hard wire the fan in the car at the ballast resistor... fan wires get pretty warm while its running - obvious the fan is pulling too much current. Turn on AC and turn everything to cool, and change floor/vent/windshield on the panel - no response. AC compressor never kicked on, blows lukewarm air (car is running at normal temp according to dash temp gauge)

Anyone know what is going on?

Can anyone tell me which plug to pull codes from, and what the codes are? (checked bay13 and google, no findings)

Any help would be MUCH appreciated

thanks
Caleb

Post by **matthew1** » 07 Nov 2005, 16:24

How to get codes
http://www.troublecodes.net/Volvo/

clt850guy · Post by **clt850guy** » 07 Nov 2005, 18:02

Well, it's bad.

Found a section in my Haynes manual about A/C diagnostic... SUPRISE!

Pulled a WORLD of codes...

Screw the codes and lets break stuff! jk

Pulled the A/C control panel out... it wreaked of burnt electronics.

On the inside: 4 fried capacitors right in a row.

Obviously the control panel is dead... but what caused it to die? If it were the fan, wouldn't it be the ballast resistor that died? Ballast resistor still seems good, no burnt components. Fan seems to run ok, but still the wires get quite warm when its hard wired... high fan current was also in the code list.

Replace fan motor: Yes/no
Replace ballast resistor: Yes/no

Thanks
Caleb