Diagnostic Mode 3: Check DTC Memory

1999 Volkswagen Cabrio (1V7) L4-2.0L (ABA)SECTION 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 a DTC entry.

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






Procedure
- Connect diagnostic tester.
- 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 test procedure:

Note: "Emission"-relevant malfunctions are additionally indicated in the instrument cluster via the exhaust 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) or by the Transmission Control Module (ECM).

- Erase DTC memory after repairing malfunction.

Display example:
P0444 Evaporative Emission (EVAP) Canister Purge Regulator ValveCircuit Open

Explanation:
P0444 = SAE diagnostic trouble code (malfunction identification number).
Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80- = malfunctioning wiring path or malfunctioning component.
Open circuit = Malfunction type as text
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.