HELP! Malfunctioning air conditioning on 2000 CLK 320 Coupe!
07-06-2004, 01:46 PM
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HELP! Malfunctioning air conditioning on 2000 CLK 320 Coupe!
My 2000 CLK 320 coupe recently had the check engine light go off. The MAS was replaced under warranty.
Ever since, the air conditioning has been acting up. After being parked overnight or for 8 hours at work, the vents only blow uncooled air out! Even at the lowest setting, no cold air comes out. This is true even if the car is driven for 30 minutes.
However, if I drive for 10 minutes, stop and go get groceries (for example), and then restart the car, the air conditioning will blast cold air at me. So it would seem that the actual air conditioning works, but there's something wrong with a sensor?
Anybody able to shed light on this problem? Any help would be greatly appreciated!
Ever since, the air conditioning has been acting up. After being parked overnight or for 8 hours at work, the vents only blow uncooled air out! Even at the lowest setting, no cold air comes out. This is true even if the car is driven for 30 minutes.
However, if I drive for 10 minutes, stop and go get groceries (for example), and then restart the car, the air conditioning will blast cold air at me. So it would seem that the actual air conditioning works, but there's something wrong with a sensor?
Anybody able to shed light on this problem? Any help would be greatly appreciated!
07-07-2004, 12:11 PM
#2
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A/C reset/resynch....
Do you have the Climatronic (digital) unit? You can do a system check, diagnosis, and reset of the registers by pressing and holding the 'defrost' and 'recirc' buttons together....and release when the lights on both buttons alternately flash. The test runs for 15 - 20 seconds and when the lights stop flashing it's over.
Last edited by mleskovar; 07-07-2004 at 12:23 PM.
07-07-2004, 08:00 PM
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Which defrost?
Originally Posted by mleskovar
Do you have the Climatronic (digital) unit? You can do a system check, diagnosis, and reset of the registers by pressing and holding the 'defrost' and 'recirc' buttons together....and release when the lights on both buttons alternately flash. The test runs for 15 - 20 seconds and when the lights stop flashing it's over.
07-13-2004, 11:06 PM
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Ok, did a bit of reading on this board and ran the diagnostic using the climate control. I had to press and hold the "REST" button and use the "AUTO" button to scroll. Unfortunately, as Murphy's Law goes, the time I want to run the diagnostic is the time when the A/C has been functioning NORMALLY for the last 2 days!
1 (in car temp) 28
2 (outside temp) 30
3 (heater core temp L) 16
4 (heater core temp R) 15
5 (evaporator core temp) 5
6 (engine coolant temp) 88
7 (refrigerant pressure) 4
8 (refrigerant temp) 35
9 (not used) 0
10 (blower control voltage) 1.2
20 (control current of aux fan) 0
21 (engine RPM) 7
22 (vehicle speed) 0
23 (terminal 58d battery charge) 0
24 (battery voltage) 14.0
40 (software status register) 8
41 (hardware status register) 5
42 (???) 232
43 (???) 30
EDIT: Ok, the A/C just malfunctioned. The Evap Temp Sensor said 19 and wouldn't get any lower while the fan just blew warm air at me. Then after 15 mintues, suddenly the A/C turned on, blasted freezing cold air, and then the sensor said 3!!!
Can anybody make sense of this? Is it the A/C Evap Temp Sensor that's the problem?
Help is greatly appreciated!!
1 (in car temp) 28
2 (outside temp) 30
3 (heater core temp L) 16
4 (heater core temp R) 15
5 (evaporator core temp) 5
6 (engine coolant temp) 88
7 (refrigerant pressure) 4
8 (refrigerant temp) 35
9 (not used) 0
10 (blower control voltage) 1.2
20 (control current of aux fan) 0
21 (engine RPM) 7
22 (vehicle speed) 0
23 (terminal 58d battery charge) 0
24 (battery voltage) 14.0
40 (software status register) 8
41 (hardware status register) 5
42 (???) 232
43 (???) 30
EDIT: Ok, the A/C just malfunctioned. The Evap Temp Sensor said 19 and wouldn't get any lower while the fan just blew warm air at me. Then after 15 mintues, suddenly the A/C turned on, blasted freezing cold air, and then the sensor said 3!!!
Can anybody make sense of this? Is it the A/C Evap Temp Sensor that's the problem?
Help is greatly appreciated!!
Last edited by A.Emgee; 07-14-2004 at 08:37 PM.
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07-15-2004, 12:16 AM
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209/W210 Estate /W211 modded by MBENZNL
I Would REPLACE the Evap temp sensor....
They do the Hide and seek Somtimes ok other No Bueno
very easy to replace order the sensor from the parts stop On Mercedesshop.com and remove the LEFT underdash panel..the sensor is in the Evap case Center of dash area...
I Did SEVERAL when I was at Mercedes....
Only other way to check would be with the Star diag ..a code would be stored in the Climate control system
They do the Hide and seek Somtimes ok other No Bueno
very easy to replace order the sensor from the parts stop On Mercedesshop.com and remove the LEFT underdash panel..the sensor is in the Evap case Center of dash area...
I Did SEVERAL when I was at Mercedes....
Only other way to check would be with the Star diag ..a code would be stored in the Climate control system
07-20-2004, 08:27 PM
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Not a Benzer anymore
For the A/C Diagnostic Codes...
Are there any guidelines or ranges of what should be where...
EG: If the outside temp is 80 with no humidity... what should the values be for the refrige temp... Etc etc.
EG: If the outside temp is 80 with no humidity... what should the values be for the refrige temp... Etc etc.
07-26-2004, 11:58 AM
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Originally Posted by MARK CUMMINS
I Would REPLACE the Evap temp sensor....
They do the Hide and seek Somtimes ok other No Bueno
very easy to replace order the sensor from the parts stop On Mercedesshop.com and remove the LEFT underdash panel..the sensor is in the Evap case Center of dash area...
I Did SEVERAL when I was at Mercedes....
Only other way to check would be with the Star diag ..a code would be stored in the Climate control system
They do the Hide and seek Somtimes ok other No Bueno
very easy to replace order the sensor from the parts stop On Mercedesshop.com and remove the LEFT underdash panel..the sensor is in the Evap case Center of dash area...
I Did SEVERAL when I was at Mercedes....
Only other way to check would be with the Star diag ..a code would be stored in the Climate control system
Error codes:
B1234: Sun sensor
B1421: Cycle module
What now?
07-26-2004, 08:07 PM
#12
Intermittent A/C operation has been traced to something else too. Not only the evap temp sensor, but some programming in the a/c module. I am not entirely sure of your model, but it probably does have an option in the version coding for "Refrigerant level check". You want this turned OFF. My dealer has been fixing a bunch of intermittent a/c problems by adjusting this coding. Until recently all cars we have gotten, for years, have had this turned on. Now they come with it turned off.... We also check this during PDI and services. Basically any time a laptop is hooked up we check this setting and change it if it is on.
07-27-2004, 07:31 PM
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Originally Posted by saturnstyl
Intermittent A/C operation has been traced to something else too. Not only the evap temp sensor, but some programming in the a/c module. I am not entirely sure of your model, but it probably does have an option in the version coding for "Refrigerant level check". You want this turned OFF. My dealer has been fixing a bunch of intermittent a/c problems by adjusting this coding. Until recently all cars we have gotten, for years, have had this turned on. Now they come with it turned off.... We also check this during PDI and services. Basically any time a laptop is hooked up we check this setting and change it if it is on.
