w245 Heater fan - only works on "5" or is very quiet?
Discussion
Sounds like your front scuttle area has filled with water due to a blocked drain bung. Ifd you lift the bonnet & look at the scuttle trim panel below the wipers you'll see a trim panel in the middle that covers the pollen/dust filter. Unclip the cover & remove the filter then look down the bottom & you'll see a black grommet type drain bung. It'll almost certainly be blocked preventing water from draining out. The water eventually builds up & then overflows into the inside of the heater box via the air duct flooding the heater blower fan & blower fan resistor pack assembly causing it to short circuit/corrode & basically fail. If the drain has been blocked for some time & the vehicles been in a lot of rain etc you may find the floor carpets are wet as well.
I've come across this problem several times of recent & basically have removed the offending drain grommet, cleaned out the scuttle area & then replaced the blower fan & blower fan resistor control pack.
I've come across this problem several times of recent & basically have removed the offending drain grommet, cleaned out the scuttle area & then replaced the blower fan & blower fan resistor control pack.
mbtech01 said:
Sounds like your front scuttle area has filled with water due to a blocked drain bung. Ifd you lift the bonnet & look at the scuttle trim panel below the wipers you'll see a trim panel in the middle that covers the pollen/dust filter. Unclip the cover & remove the filter then look down the bottom & you'll see a black grommet type drain bung. It'll almost certainly be blocked preventing water from draining out. The water eventually builds up & then overflows into the inside of the heater box via the air duct flooding the heater blower fan & blower fan resistor pack assembly causing it to short circuit/corrode & basically fail. If the drain has been blocked for some time & the vehicles been in a lot of rain etc you may find the floor carpets are wet as well.
I've come across this problem several times of recent & basically have removed the offending drain grommet, cleaned out the scuttle area & then replaced the blower fan & blower fan resistor control pack.
thanks, I'll investigate. However, fan does work. On top setting its really powerfull... I've come across this problem several times of recent & basically have removed the offending drain grommet, cleaned out the scuttle area & then replaced the blower fan & blower fan resistor control pack.
Shoestringracer said:
thanks, I'll investigate. However, fan does work. On top setting its really powerfull...
If the fan works on top speed then its most likely just the fan speed resistor pack assembly. You'll find it located on the righthand side of the heater box down by where the clutch pedal normally sits if it's a manual. It'll have an electrical connector plug with around four wires plugged into it.mbtech01 said:
Shoestringracer said:
thanks, I'll investigate. However, fan does work. On top setting its really powerfull...
If the fan works on top speed then its most likely just the fan speed resistor pack assembly. You'll find it located on the righthand side of the heater box down by where the clutch pedal normally sits if it's a manual. It'll have an electrical connector plug with around four wires plugged into it.mbtech01 said:
Sounds like your front scuttle area has filled with water due to a blocked drain bung. Ifd you lift the bonnet & look at the scuttle trim panel below the wipers you'll see a trim panel in the middle that covers the pollen/dust filter. Unclip the cover & remove the filter then look down the bottom & you'll see a black grommet type drain bung. It'll almost certainly be blocked preventing water from draining out. The water eventually builds up & then overflows into the inside of the heater box via the air duct flooding the heater blower fan & blower fan resistor pack assembly causing it to short circuit/corrode & basically fail. If the drain has been blocked for some time & the vehicles been in a lot of rain etc you may find the floor carpets are wet as well.
I've come across this problem several times of recent & basically have removed the offending drain grommet, cleaned out the scuttle area & then replaced the blower fan & blower fan resistor control pack.
Thanks for your detilaed reply. The CD changer in the glove box is also not working and seems not to have power - nothing lights up. Could this be related? I've come across this problem several times of recent & basically have removed the offending drain grommet, cleaned out the scuttle area & then replaced the blower fan & blower fan resistor control pack.
va1o said:
Shoestringracer said:
The CD changer in the glove box is also not working and seems not to have power - nothing lights up. Could this be related?
Are you sure it's a Changer? A lot of them have a 4-slot holder which looks like a Changer but doesn't offer disk playback as its only for storage.Shoestringracer said:
mbtech01 said:
Sounds like your front scuttle area has filled with water due to a blocked drain bung. Ifd you lift the bonnet & look at the scuttle trim panel below the wipers you'll see a trim panel in the middle that covers the pollen/dust filter. Unclip the cover & remove the filter then look down the bottom & you'll see a black grommet type drain bung. It'll almost certainly be blocked preventing water from draining out. The water eventually builds up & then overflows into the inside of the heater box via the air duct flooding the heater blower fan & blower fan resistor pack assembly causing it to short circuit/corrode & basically fail. If the drain has been blocked for some time & the vehicles been in a lot of rain etc you may find the floor carpets are wet as well.
I've come across this problem several times of recent & basically have removed the offending drain grommet, cleaned out the scuttle area & then replaced the blower fan & blower fan resistor control pack.
Thanks for your detilaed reply. The CD changer in the glove box is also not working and seems not to have power - nothing lights up. Could this be related? I've come across this problem several times of recent & basically have removed the offending drain grommet, cleaned out the scuttle area & then replaced the blower fan & blower fan resistor control pack.
I've cleared the blockage but this time the bung fell off and is sitting on the starter motor and therefore out of reach. I've tested that water will flow out of the pollen filter housing and into the engine bay (better than into the cabin) but am worried about sucking air in! Is there a way to replace the bung?
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