W221 Climate Control Disabled
09-27-2015, 09:17 PM
#1
Member
Thread Starter
W221 Climate Control Disabled
So last night drove for about 5 hours no problems. This morning, I noted that upon starting the car that the (front) blower motor was not blowing. The rear blower motor is working fine. I also noted that the air-conditioning was not cooling. Apparently the compressor is disabled. The climate control functions in COMAND are operational (temperature, defrost, fan setting) but no forced air discharge from front registers. The A/C lines under the hood are not cooling and there is no condensation drip under the car. However, the A/C OFF is not displayed like it would if the compressor was shut down by the computer when the refrigerant is low. The rear climate control and fan is working fine/blowing, however, the air is not being cooled (because the compressor function is disabled.)
I checked fuse 54 under the hood and it's fine, but I replaced it anyway just to be certain - no change.
I'm at a loss pending the dealership. The only thing I can imagine is that perhaps the blower regulator gave up the ghost and that created some kind of climate control error code in the climate control computer which has subsequently disabled the compressor. Anyone able to put any credence to that theory OR offer what the problem(s)/resolution(s) may be?
I checked fuse 54 under the hood and it's fine, but I replaced it anyway just to be certain - no change.
I'm at a loss pending the dealership. The only thing I can imagine is that perhaps the blower regulator gave up the ghost and that created some kind of climate control error code in the climate control computer which has subsequently disabled the compressor. Anyone able to put any credence to that theory OR offer what the problem(s)/resolution(s) may be?
09-28-2015, 06:35 AM
#2
So last night drove for about 5 hours no problems. This morning, I noted that upon starting the car that the (front) blower motor was not blowing. The rear blower motor is working fine. I also noted that the air-conditioning was not cooling. Apparently the compressor is disabled. The climate control functions in COMAND are operational (temperature, defrost, fan setting) but no forced air discharge from front registers. The A/C lines under the hood are not cooling and there is no condensation drip under the car. However, the A/C OFF is not displayed like it would if the compressor was shut down by the computer when the refrigerant is low. The rear climate control and fan is working fine/blowing, however, the air is not being cooled (because the compressor function is disabled.)
I checked fuse 54 under the hood and it's fine, but I replaced it anyway just to be certain - no change.
I'm at a loss pending the dealership. The only thing I can imagine is that perhaps the blower regulator gave up the ghost and that created some kind of climate control error code in the climate control computer which has subsequently disabled the compressor. Anyone able to put any credence to that theory OR offer what the problem(s)/resolution(s) may be?
I checked fuse 54 under the hood and it's fine, but I replaced it anyway just to be certain - no change.
I'm at a loss pending the dealership. The only thing I can imagine is that perhaps the blower regulator gave up the ghost and that created some kind of climate control error code in the climate control computer which has subsequently disabled the compressor. Anyone able to put any credence to that theory OR offer what the problem(s)/resolution(s) may be?
Might help.
https://mbworld.org/forums/s-class-w221/600495-hvac-blower-motor-not-working-s550-fix.html
09-28-2015, 10:47 AM
#3
if your squirrel cage fan has seized you will have the behavior you are describing.
turn on the air conditioning. hit couple times the underdash on the pass side. the fan might or might not start. if it does - it is your fan that needs cleaning/ lubrication or replacement. if it doesnt start i would still disassemble the fan enclosure and test the fan motor
if fan is good the car needs to be read via star/ das
turn on the air conditioning. hit couple times the underdash on the pass side. the fan might or might not start. if it does - it is your fan that needs cleaning/ lubrication or replacement. if it doesnt start i would still disassemble the fan enclosure and test the fan motor
if fan is good the car needs to be read via star/ das
