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Diagnostic Mode 3: Check DTC Memory



Diagnostic Mode 3: Check DTC Memory

Function
This diagnostic mode indicates all stored DTCs of components and systems which are emission relevant.

Malfunction Indicator Lamp (MIL) in instrument cluster lights up for one DTC entry.

SAE Diagnostic Trouble Codes (DTCs)
The DTC always consists of a 5-digit alphanumeric value with the following meaning:

Component group:
- Pxxxx = DTC for drivetrain.

Norm-Code:
- P0xxx = trouble codes defined by SAE with specified malfunction texts.
- P1xxx = additional emission relevant DTCs provided by manufacturer.
- P2xxx = DTCs defined by SAE with specified texts, from MY 2000
- P3xxx = additional emissions relevant DTCs provided by manufacturer from MY 2000.

Repair group
- Px0xx = Fuel-air mixture and additional emission regulations
- Px1xx = Fuel and air ratio.
- Px2xx = Fuel and air ratio.
- Px3xx = Ignition system.
- Px4xx = additional emission regulation.
- Px5xx = Speed and idle control.
- Px6xx = Control module and output signals.
- Px7xx = Transmission.
- Px8xx = Transmission.
- Px9xx = Control modules, input and output signals.

Procedure
- Connect diagnostic tester. Diagnostic Tester, Connecting
- Start engine and let run at idle.

NOTE:
Only if engine does not start:
- Operate starter for approx. 6 seconds. Do not switch ignition off afterward.

- Under address word 33, select "Diagnostic mode 3: , Check DTC memory."
The number of stored malfunctions or "0 malfunctions detected" is displayed.
- End diagnosis and switch ignition off.
- Repair stored malfunctions according to DTC table:
- SAE P0xxx-DTCs, P0010
- SAE P1xxx-DTCs, P1102
- SAE P2xxx-DTCs, P2096
- SAE P3xxx-DTCs. P3081

- Erase DTC memory, Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data

NOTE:
- The DTC table is sorted by SAE codes.
- "E-Gas"-relevant malfunctions are also indicated by the warning lamp for Electronic Power Control ("EPC warning lamp") in the instrument cluster.
- In addition, "emission"-relevant malfunctions are indicated in the instrument cluster via the Malfunction Indicator Lamp (MIL).
- In diagnostic mode 2, it can be determined at which operating condition a malfunction was detected and stored by the Engine Control Module (ECM), diagnostic mode 2: Checking operating conditions. Diagnostic Mode 2: Check Operating Conditions
- Erase DTC memory after repairing malfunction, diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data

Display example:
P0444 Evaporative Emission System Purge Control Valve Circuit Open

Explanation:
- P0444 = SAE diagnostic trouble code (malfunction identification number).
- Evaporative Emission System Purge Control Valve = malfunctioning wiring path or malfunctioning component.
- Circuit Open = Malfunction type as text