Reading and Clearing Diagnostic Trouble Codes

Diagnosis - Diagnostic Trouble Code (DTC) Memory [12]

Test Preparation for DTC Readout

Note: A stored DTC is erased, if the connector of the 4MATIC control module (N30/3) is unplugged or if the battery is disconnected.

Figure 1 -- Connection Diagram - Impulse Counter Scan Tool:

1. Connect impulse counter scan tool to data link connector (X11/4).

Note: Connect yellow wire from impulse counter scan tool as follows:
4MATIC control module (N30/3) -- socket 5

2. Engine: At idle.

3. Read DTC memory of 4MATIC control module (N30/3). Scan Tool Testing and Procedures

Note: After successful repair erase DTC memory with engine running. The following faults are not stored by the 4MATIC control module:
- 4MATIC function indicator lamp (A1e25) defective.
- 4MATIC MIL (A1e24) defective.
- Oil pressure switch (A7/2s1) defective.

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