DTC Memory, Interrogating
DTC Memory, Interrogating
=> [ DTC Table ]
=> [ DTC Table through DTC 00975 ]
=> [ DTC Table from DTC 01044 ]
• The Climatronic control module (J255) A/C control head automatically switches to the "Econ" operating mode if no basic setting was performed after installation of a new Climatronic control module (J255) A/C control head, or the pressure measured by the high pressure sensor (G65) is too low or too high (the compressor may not be switched on). As of hardware/software version "0711", this status is displayed as a fault.
• If the Climatronic control module (J255) A/C control head automatically switches to the "Off" operating mode after the ignition is activated and only the "Def" operating mode can be set with the ignition on (other settings not possible). In this case, for example the ignition was switched on with a key that was not activated for this vehicle or the instrument cluster control module ( J285) does not send the key number via the comfort data bus system (as of hardware/software version "0711").
• If a number is shown in the display of the Climatronic control module (J255) A/C control head query the DTC memory of the Climatronic control module (J255) A/C control head (for example, the number "60" indicates a fault in the interior temperature sensor fan (V42)). If the display of the Climatronic control module (J255) A/C control head is flashing and if no fault is displayed in the DTC memory (e.g. display " 09"), there is a fault in the electronics of the Climatronic control module (J255) A/C control head.
- With the ignition switched off, connect the Vehicle Diagnosis, Testing and Information System (VAS 5051A) e.g. with the diagnostic cable (VAS 5051/5A) and the K-wire adapter (VAS 6017B) (or the K-wire adapter (VAS 6017A)) to the 16-pin data link connector (DLC) of the vehicle and select the air conditioner/heater electronics with address word " 08". Refer to => [ VAS 5051A, Connecting and Selecting Functions ] VAS 5051A, Connecting and Selecting Functions.
Indication on display of Vehicle Diagnosis, Testing and Information System (VAS 5051A):
- Select "02 - Check DTC memory" function.
Indication on display of Vehicle Diagnosis, Testing and Information System (VAS 5051A):
• Display field - 1 - indicates the number of stored malfunctions.
• Display field - 2 - indicates the DTC, the malfunction location and malfunction type of the saved DTC.
• By clicking the <- button, you will return to the selection menu.
• If no fault has been detected but the A/C system is not operating properly (e.g. always or temporarily no cooling power, unsatisfactory system regulation, no regulation of the fresh air blower speed, the Climatronic control module (J255) A/C control head always switches to the " Econ" or "Off" operating mode):
• 1. Read measured value block (function 08).
• 2. Perform output diagnostic test mode (function 03). Refer to => [ Final Control Diagnosis ] Final Control Diagnosis.
• 3. A/C system cooling performance, checking => [ A/C Unit, Checking Cooling Output ] A/C Unit, Checking Cooling Output
• If fault(s) are found:
• 1. Eliminate fault.
• 2. Check the DTC memory (function 02).
• 3. Erase fault memory (function 05).
• 4. Check the coding of the Climatronic control module (J255) A/C control head or the instrument cluster control module (J285). Refer to => [ A/C Control Head Climatronic Control Module, Coding ] A/C Control Head Climatronic Control Module, Coding.
• 5. Perform basic setting (function 04).
• 6. Check the DTC memory (function 02), eliminate faults displayed if necessary, erase fault memory (function 05) and repeat procedure.
• 7. End output (function 06).
Indication on display of Vehicle Diagnosis, Testing and Information System (VAS 5051A):
- End output (function 06). Refer to => [ Ending Output ] Erasing DTC Memory, Ending Output.
- Switch off ignition and unplug diagnostic connector.