2004 CLK320 front A/C blower not working.
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CLK 320
2004 CLK320 front A/C blower not working.
History . . . About 2 yrs ago my front A/C-Heater fan wouldn't come on unless I turned the fan control to "O" before shutting off the engine. Got used to it and read up in the forums that the blower resistor (regulator) located within the fan housing was likely the culprit. I ordered a new "Behr" brand resistor and waited for the blower to fail completely.
About a yr ago a loud "clicking" sound could be heard (and felt) from beneath the pilots side dash at about once a one second interval and lasting for about a min after turning off the ignition. This has been intermittant. My mech sugested it was a duct/vent door servo, however the A/C-Heater blower was still working as long as I turned it off before shutting the engine off.
So last week the front blower finally failed yet the rear fan still worked and made cold or hot air as selected. I replaced the resistor, no help. The original blower motor (made by Behr) showed evidence the brushes were gone (car has 140K on it) so I replaced it w/ a TYC brand (#700190 oem # 203 820 25 14) from Amazon (so it must be Chinese
and still no help.
I did a bit more reading within the forums and then tried an "ACC" reset by holding the defrost & recirc buttons together . . . I got the continous alternating lights and heard the same "clicking" beneath the dash coming from more than one location . . . still no help . . . I miss my A/C
Anyone ?
About a yr ago a loud "clicking" sound could be heard (and felt) from beneath the pilots side dash at about once a one second interval and lasting for about a min after turning off the ignition. This has been intermittant. My mech sugested it was a duct/vent door servo, however the A/C-Heater blower was still working as long as I turned it off before shutting the engine off.
So last week the front blower finally failed yet the rear fan still worked and made cold or hot air as selected. I replaced the resistor, no help. The original blower motor (made by Behr) showed evidence the brushes were gone (car has 140K on it) so I replaced it w/ a TYC brand (#700190 oem # 203 820 25 14) from Amazon (so it must be Chinese
and still no help. I did a bit more reading within the forums and then tried an "ACC" reset by holding the defrost & recirc buttons together . . . I got the continous alternating lights and heard the same "clicking" beneath the dash coming from more than one location . . . still no help . . . I miss my A/C
Anyone ?
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The clicking noises have nothing to do with the blower problem. One of the servos/linkage sets (I think there are 9 of them, IIRC) has failed. You need to get codes read from the ACC to know which. Some are a PITA to get to, some are "crazy-ridiculous" meaning pulling the dash, heater core and A/C evaporator.
As for the blower, it's possible that your replacement parts are bad. Did you try bench testing them?
As for the blower, it's possible that your replacement parts are bad. Did you try bench testing them?
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CLK 320
Thx for your input. Yea Rudeney, I thought any connection between the "clicking" I'm hearing on shutdown and the fwd fan crapping out on me was a stretch, but thought maybe Mercedes has possibly used an ECS computer (environmental ctrl sys) and possibly could tie these faults together. I did read in the forums where someone had replaced their OAT sensor (outside air temp) and the A/C began working again on a different model Benz.
Yes it's possible the new blower is "bad from stock" and I'm going to pull it again to check operation on 12v. But even more telling may be to see if there's power to the plug. The old blower had no brushes left on the commutator so I thought replacing the blower assy would solve this. I'm tempted to just replace the brushes in the old blower motor if im getting power to the plug comming out of the chassis.
Of coarse I did ohm out the two fuses shown tied to the A/C-Heater blower and they checked good. One is in the cabin @ 15A, the other is in the engine comp @ 7.5A. I think I'll just replace those anyways, just because they ohm out OK doesn’t mean they will carry current.
I'd sure like to find a diagram showing what all the relays under the hood and trunk are for. I suspect there's more to this blower control than a resistor and two fuses.
bw
Yes it's possible the new blower is "bad from stock" and I'm going to pull it again to check operation on 12v. But even more telling may be to see if there's power to the plug. The old blower had no brushes left on the commutator so I thought replacing the blower assy would solve this. I'm tempted to just replace the brushes in the old blower motor if im getting power to the plug comming out of the chassis.
Of coarse I did ohm out the two fuses shown tied to the A/C-Heater blower and they checked good. One is in the cabin @ 15A, the other is in the engine comp @ 7.5A. I think I'll just replace those anyways, just because they ohm out OK doesn’t mean they will carry current.
I'd sure like to find a diagram showing what all the relays under the hood and trunk are for. I suspect there's more to this blower control than a resistor and two fuses.
bw
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This includes relays (it's for the W203, but is essentially the same on the W209):
http://benzbits.com/w203/fuses.html
http://benzbits.com/w203/fuses.html
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CLK 320
Again, thx for your input Rodney . . . Big News ! You were on to the fix, turns out the new resistor I'd installed into the new blower assy WAS "bad from stock" so I installed the old old resistor and Ta Da ! I am enjoying A/C again. The problem was only within the blower motor. This chinese blower seems to be balanced well enough and runs quietly foronow ; ) Time will tell.
Thank You for the relay diagram intel, I'm sure it will pay off as iintsnd to keep this car ! : )
bw
Thank You for the relay diagram intel, I'm sure it will pay off as iintsnd to keep this car ! : )
bw
