Reading Diagnostic Trouble Codes

Diagnostic Mode 03 - Read DTC Memory

Function

Diagnostic Mode 03 makes it possible to read emissions-related faults (confirmed DTCs: faults which have activated the MIL) in the ECM and in the TCM.

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

Diagnostic Trouble Codes

The DTC always consists of a 5-digit alpha-numeric value with the following meaning:













Procedure

- Connect Scan Tool.

- Start engine and let run at idle.

• 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 => [ SAE P0xxx Diagnostic Trouble Codes ] Testing and Inspection,

• SAE P1xxx-DTCs => [ SAE P1xxx Diagnostic Trouble Codes ] Testing and Inspection,

• SAE P2xxx-DTCs => [ SAE P2xxx Diagnostic Trouble Codes ] Testing and Inspection.

• SAE P3xxx-DTCs => [ SAE P3xxx Diagnostic Trouble Codes ] Testing and Inspection,

• SAE U0xxx-DTCs => [ SAE U0xxx Diagnostic Trouble Codes ] Testing and Inspection.

• The DTC table is sorted by SAE codes.

• "Emission" relevant malfunctions are additionally 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 02 - Read Operating Conditions ] Diagnostic Mode 02 - Read Operating Conditions

• Erase DTC memory after repairing malfunction => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory

Display Example

P0183 Fuel Temperature Sensor A Circuit High

Explanation

• P0183 = SAE diagnostic trouble code (malfunction identification number).

• Fuel Temperature Sensor A = faulty circuit or malfunctioning component.

• Circuit High = malfunction type as text