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Diagnostic Mode 3: Check DTC Memory



Mode 3: Check DTC Memory

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

Malfunction Indicator Lamp (MIL) -K83- in instrument cluster lights up for one DTC entry.

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

Component group
P x x x x DTC for drivetrain

Norm-Code
P 0 x x x DTCs defined by SAE with specified malfunction texts
P 1 x x x additional emission relevant DTCs provided by manufacturer
P 2 x x x DTCs defined by SAE with specified texts, from MY 2000
P 3 x x x additional emissions relevant DTCs provided by manufacturer from MY 2000

Repair group
P x 0 x x Fuel and air mixture and additional emission regulations
P x 1 x x Fuel and air ratios
P x 2 x x Fuel and air ratios
P x 3 x x Ignition system
P x 4 x x Additional exhaust regulation
P x 5 x x Speed and idle control
P x 6 x x Control module and output signals
P x 7 x x Transmission
P x 8 x x Transmission
P x 9 x x Control modules, input and output signals

Check DTC Memory

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

NOTE: If the engine does not start up, crank engine using starter for at least 5 seconds, do not switch off ignition afterward under any circumstances.

- In diagnostic function "33 - OBD", select "Mode 3: Check DTC memory."

The number of stored malfunctions or "0 malfunctions detected" is displayed.

NOTE:
- The DTC tables are sorted by SAE code.
- Stored malfunctions of Engine Control Module (ECM) are displayed under "10 - Engine electronics" and stored malfunctions of Transmission Control Module (TCM) are displayed under "1A - Transmission electronics".
- In addition, "emission"-relevant malfunctions are indicated in the instrument cluster via the Malfunction Indicator Lamp (MIL) -K83-.
- E-Gas -relevant malfunctions are also indicated by the Electronic Power Control (EPC) Warning Lamp -K132- ("EPC warning lamp") in the instrument cluster.
- In "Mode 2: Check operating conditions", it can be determined at which operating condition the Engine Control Module detected and stored a malfunction. Diagnostic Mode 2: Check Operating Conditions

Indication example Explanation
P0444 SAE Diagnostic Trouble Code (DTC)
EVAP canister purge regulator valve -N80- malfunctioning wiring path or malfunctioning component
Open circuit Malfunction type as text

- Repair stored malfunction(s) according to DTC table:
- SAE P0xxx-DTCs P0102
- SAE P1xxx-DTCs P1102

Final procedures

The following work steps must be performed in the described sequence after the malfunction(s) have been repaired:
1 - Check DTC memory "Mode 3: Check DTC memory".
2 - If necessary, erase DTC memory "Mode 4: Reset/erase diagnostic data". Diagnostic Mode 4: Reset/Erase Diagnostic Data
3 - Generate readiness code. Readiness Code, Generating

- End diagnosis and switch ignition off.