C43 - climate control issue
Discussion
The climate control on my '99 C43 is often reluctant to get started - it will be set to 'auto' but but the fans don't come on and I'm left to bake for 5-10 minutes.
I've tried manually adjusting the fan, or turning the system off and on again. Sometimes it helps, other times it doesn't.
Does having the windows down affect the system at all?
Anyone have any ideas?
Thanks
I've tried manually adjusting the fan, or turning the system off and on again. Sometimes it helps, other times it doesn't.
Does having the windows down affect the system at all?
Anyone have any ideas?
Thanks
Air con is less effective with the windows open but the system does not respond differently.
Could you describe the symptoms with a little more detail?
Is this happening?
Display shows fans are set to high speed, you can hear fans turning, but no air (cold or otherwise) is coming out of the vents? All works fine (but air is not chilled) when set to "EC"?
If so, your evaporator temperature sensor has failed. This is a common fault on this system. It is also cheap and easy to replace.
Have you obtained the diagnostic information from the dashboard control unit? (Press and hold "rest" for about 12 seconds in order to do so, then press + or - in order to move through the different values.)
Could you describe the symptoms with a little more detail?
Is this happening?
Display shows fans are set to high speed, you can hear fans turning, but no air (cold or otherwise) is coming out of the vents? All works fine (but air is not chilled) when set to "EC"?
If so, your evaporator temperature sensor has failed. This is a common fault on this system. It is also cheap and easy to replace.
Have you obtained the diagnostic information from the dashboard control unit? (Press and hold "rest" for about 12 seconds in order to do so, then press + or - in order to move through the different values.)
r129sl said:
Air con is less effective with the windows open but the system does not respond differently.
Could you describe the symptoms with a little more detail?
Is this happening?
Display shows fans are set to high speed, you can hear fans turning, but no air (cold or otherwise) is coming out of the vents? All works fine (but air is not chilled) when set to "EC"?
If so, your evaporator temperature sensor has failed. This is a common fault on this system. It is also cheap and easy to replace.
Have you obtained the diagnostic information from the dashboard control unit? (Press and hold "rest" for about 12 seconds in order to do so, then press + or - in order to move through the different values.)
Thanks for this info. Those aren't the symptoms though. I will try to obtain the diagnostic info. Could you describe the symptoms with a little more detail?
Is this happening?
Display shows fans are set to high speed, you can hear fans turning, but no air (cold or otherwise) is coming out of the vents? All works fine (but air is not chilled) when set to "EC"?
If so, your evaporator temperature sensor has failed. This is a common fault on this system. It is also cheap and easy to replace.
Have you obtained the diagnostic information from the dashboard control unit? (Press and hold "rest" for about 12 seconds in order to do so, then press + or - in order to move through the different values.)
The display does show that the fans should be on but they're not, at all. After a little while, if you put your hand right to the vent you feel cold air. Perhaps it's just the fans that aren't turning on, and as a result it takes some time for cool air to get to the vents?
Sometimes the fans come on straightaway when I start the car; other times, they don't come on at all during a short drive.
Fiddling around with the settings does not seem to make any difference (e.g. switching to EC, adjusting fan speed manually, turning off completely, going back to Auto, adjusting the temp)
I've had something similar to this, actually. Sometimes--very rarely--the fans just do not come on when the car is started. I usually notice when it gets too hot. Turning the engine ona nd off ususually does the trick for me. I would like to knwo the cause.
YOu can get diagnostic information out of the push button control unit in the dash quite easily. This link gives some detail:
http://www.peachparts.com/shopforum/showthread.php...
YOu can get diagnostic information out of the push button control unit in the dash quite easily. This link gives some detail:
http://www.peachparts.com/shopforum/showthread.php...
Don't know if this helps, but copied this from a C36+C43 forum in the USA:
DIAGNOSTIC TROUBLE CODE READOUT
Entering Diagnostic Trouble Code (DTC) Display Mode
1) Turn ignition on. Press down arrow push button until "LO" is shown in A/C-heater control panel temperature display window.
2) Within 20 seconds, simultaneously press REST and defrost push buttons for more than 2 seconds. The Light Emitting Diode (LED) in the recirculated air push button will blink and the display window will show "di R".3) Press AUTO push button repeatedly, recording each DTC,until all DTCs are displayed. Permanent malfunctions are displayed first. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION tables.
4) If no permanent malfunctions are stored, the display window shows "En d". Press AUTO push button again. Intermittent DTCs will be displayed. Intermittent malfunctions are recognizable by the degree (°) symbol displayed along with the DTC (example: "04 °").
5) If no intermittent malfunctions are stored, the display window shows "En° d". Proceed to ERASING DIAGNOSTIC TROUBLE CODES.
Erasing Diagnostic Trouble Codes
1) After display window shows "En° d", press AUTO push button once again. Display window should show "dE L" (delete).
2) To erase DTCs, simultaneously press down and up arrow push buttons for more than 5 seconds. The display window should show "- --". If not erasing DTCs, press the AUTO push button. The permanent DTCs will again be displayed. Proceed to EXITING DTC DISPLAY MODE.
Exiting DTC Display Mode
Simultaneously press down and up arrow push buttons until the pre-selected temperature setting of "72 °F" is displayed. Turn ignition off.
DTC IDENTIFICATION TABLE
B1226 - In-car temperature sensor (B10/4)
B1227 - Outside temperature indicator temperature sensor (B14)
B1228 - Heater core temperature (B10/1)
B1229 - Heater core temperature (B10/1)
B1230 - Evaporator temperature sensor (B10/6)
B1231 - ECT sensor (B11/4)
B1232 - Refrigerant pressure sensor (B12)
B1233 - Refrigerant temperature sensor (B12/1)
B1234 - Sun sensor (B32)
B1235 - Emissions sensor (B31)
B1241 - Refrigerant fill
B1416 - Coolant circulation pump (M13)
B1417 - Duovalve (Y21y1), left
B1418 - Duovalve (Y21y2), right
B1419 - Electromagnetic clutch (A9k1)
B1420 - Idle speed increase
B1421 - Pulse module (N65)
B1422 - Series interface (K1) connection to instrument cluster (A1)
B1423 - Switchover valve block (Y11)
B1424 - Activated charcoal filter actuator (A32m2) open
B1425 - Activated charcoal filter actuator (A32m2) closed
B1432 - Non-USA DTC
B1459 - Series interface (K2) connection to instrument cluster (A1)
B1462 - Wide open throttle (WOT)
READING SENSOR VALUES
1) Turn ignition on. Simultaneously press down and up arrow push buttons until the pre-selected temperature setting of "72 °F" is displayed. Press the AUTO push button.
2) Press REST push button for more than 6 seconds. The display window will alternately show "01" and an in-car temperature of "72 °F", or "LO" if there is an open circuit, or "HI" if there is a short circuit.
3) By pressing the windshield air distribution push button, the next ascending test step is displayed. By pressing the footwell air distribution push button, the next descending test step is displayed. See SENSOR VALUE DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION table. Press REST push button to exit reading sensor values mode.
SENSOR VALUE DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
Code Cause/Value
01 ............................. In-Car Temperature Sensor
02 ............................ Outside Temperature Sensor
03 ........................ Heater Core Temperature Sensor
05 .................... Evaporator Core Temperature Sensor
06 ................. (1) Engine Coolant Temperature Sensor
07 .............................. (2) Refrigerant Pressure
08 ............................ (3) Blower Control Voltage
09 .......... Software Status Of A/C-Heater Control Module
15 ........................... Selected In-Car Temperature
20 ................................. Software Version Code
21 ...................................... (4) Engine Speed
22 .............................. (5) A/C Compressor Speed
23 ......................................... Vehicle Speed
50 ................................ 80.° - 00.° (Not Used)
51 ......... Number Of Actual Drive Belt Slip Recognitions
52 ......... Number Of Actual Drive Belt Slip Recognitions
(1) - A display of "12.°5" corresponds to 125 Celsius (257°F).
(2) - Refrigerant pressure is displayed in bar. One bar equals 14.5037 psi. A display of "12.°8" corresponds to 12.8 bar (185.6 psi).
(3) - A display of "16.°5" corresponds to 1.65 volts.
(4) - A display of "06.°0" to "70.°0" corresponds to 600 RPM to 7000 RPM respectively.
(5) - A display of "00.°0" to "84.°0" corresponds to 0 RPM to 8400 RPM respectively
DIAGNOSTIC TROUBLE CODE READOUT
Entering Diagnostic Trouble Code (DTC) Display Mode
1) Turn ignition on. Press down arrow push button until "LO" is shown in A/C-heater control panel temperature display window.
2) Within 20 seconds, simultaneously press REST and defrost push buttons for more than 2 seconds. The Light Emitting Diode (LED) in the recirculated air push button will blink and the display window will show "di R".3) Press AUTO push button repeatedly, recording each DTC,until all DTCs are displayed. Permanent malfunctions are displayed first. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION tables.
4) If no permanent malfunctions are stored, the display window shows "En d". Press AUTO push button again. Intermittent DTCs will be displayed. Intermittent malfunctions are recognizable by the degree (°) symbol displayed along with the DTC (example: "04 °").
5) If no intermittent malfunctions are stored, the display window shows "En° d". Proceed to ERASING DIAGNOSTIC TROUBLE CODES.
Erasing Diagnostic Trouble Codes
1) After display window shows "En° d", press AUTO push button once again. Display window should show "dE L" (delete).
2) To erase DTCs, simultaneously press down and up arrow push buttons for more than 5 seconds. The display window should show "- --". If not erasing DTCs, press the AUTO push button. The permanent DTCs will again be displayed. Proceed to EXITING DTC DISPLAY MODE.
Exiting DTC Display Mode
Simultaneously press down and up arrow push buttons until the pre-selected temperature setting of "72 °F" is displayed. Turn ignition off.
DTC IDENTIFICATION TABLE
================
B1226 - In-car temperature sensor (B10/4)
B1227 - Outside temperature indicator temperature sensor (B14)
B1228 - Heater core temperature (B10/1)
B1229 - Heater core temperature (B10/1)
B1230 - Evaporator temperature sensor (B10/6)
B1231 - ECT sensor (B11/4)
B1232 - Refrigerant pressure sensor (B12)
B1233 - Refrigerant temperature sensor (B12/1)
B1234 - Sun sensor (B32)
B1235 - Emissions sensor (B31)
B1241 - Refrigerant fill
B1416 - Coolant circulation pump (M13)
B1417 - Duovalve (Y21y1), left
B1418 - Duovalve (Y21y2), right
B1419 - Electromagnetic clutch (A9k1)
B1420 - Idle speed increase
B1421 - Pulse module (N65)
B1422 - Series interface (K1) connection to instrument cluster (A1)
B1423 - Switchover valve block (Y11)
B1424 - Activated charcoal filter actuator (A32m2) open
B1425 - Activated charcoal filter actuator (A32m2) closed
B1432 - Non-USA DTC
B1459 - Series interface (K2) connection to instrument cluster (A1)
B1462 - Wide open throttle (WOT)
READING SENSOR VALUES
1) Turn ignition on. Simultaneously press down and up arrow push buttons until the pre-selected temperature setting of "72 °F" is displayed. Press the AUTO push button.
2) Press REST push button for more than 6 seconds. The display window will alternately show "01" and an in-car temperature of "72 °F", or "LO" if there is an open circuit, or "HI" if there is a short circuit.
3) By pressing the windshield air distribution push button, the next ascending test step is displayed. By pressing the footwell air distribution push button, the next descending test step is displayed. See SENSOR VALUE DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION table. Press REST push button to exit reading sensor values mode.
SENSOR VALUE DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
Code Cause/Value
01 ............................. In-Car Temperature Sensor
02 ............................ Outside Temperature Sensor
03 ........................ Heater Core Temperature Sensor
05 .................... Evaporator Core Temperature Sensor
06 ................. (1) Engine Coolant Temperature Sensor
07 .............................. (2) Refrigerant Pressure
08 ............................ (3) Blower Control Voltage
09 .......... Software Status Of A/C-Heater Control Module
15 ........................... Selected In-Car Temperature
20 ................................. Software Version Code
21 ...................................... (4) Engine Speed
22 .............................. (5) A/C Compressor Speed
23 ......................................... Vehicle Speed
50 ................................ 80.° - 00.° (Not Used)
51 ......... Number Of Actual Drive Belt Slip Recognitions
52 ......... Number Of Actual Drive Belt Slip Recognitions
(1) - A display of "12.°5" corresponds to 125 Celsius (257°F).
(2) - Refrigerant pressure is displayed in bar. One bar equals 14.5037 psi. A display of "12.°8" corresponds to 12.8 bar (185.6 psi).
(3) - A display of "16.°5" corresponds to 1.65 volts.
(4) - A display of "06.°0" to "70.°0" corresponds to 600 RPM to 7000 RPM respectively.
(5) - A display of "00.°0" to "84.°0" corresponds to 0 RPM to 8400 RPM respectively
Thanks for this ^^^
I finally had a chance to get the readouts and there are no permanent malfunctions as defined above, but a bunch of intermittent DTCs which are not mentioned.
For the intermittent DTCs the little fan icon was visible and faults were (treat the 'o' as the degree sign):
41o6
41o7
41o9
42o1
45o1
45o2
45o3
45o4
45o6
Does anyone know what these mean or is it just time to take it to a specialist?
I finally had a chance to get the readouts and there are no permanent malfunctions as defined above, but a bunch of intermittent DTCs which are not mentioned.
For the intermittent DTCs the little fan icon was visible and faults were (treat the 'o' as the degree sign):
41o6
41o7
41o9
42o1
45o1
45o2
45o3
45o4
45o6
Does anyone know what these mean or is it just time to take it to a specialist?
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