Generic Scan Tool

Diagnostic Procedures

EVAP System, Checking for Leaks

Function Test

- Select the measuring value "Test-ID 01: Tank leak test" and check whether the specified value is being reached , Diagnostic mode 8: Tank leak test.

- Check specified value of tank leak test at idle.

Specified value: Test function active

• During tank leak test, Engine Control Module (ECM) limits "test function active" to approx. 12 minutes.

• If the accelerator pedal is depressed during the test, the test will be aborted.

• To repeat the tank leak test, switch ignition off and start engine again and let run 15 minutes at idle.

- End diagnosis and switch ignition off.

If a leak is detected:

- Remove right rear wheel housing liner.

- Remove Leak detection pump (LDP) (V144) and seal connection piece to EVAP canister, parts of the EVAP canister system, removing and installing.

- Repeat function test.

If malfunction persists:

- Check whether the fuel filler cap is completely closed or whether the seal leaks; replace if necessary.

- Check whether the locking rings of the Fuel Pump (FP) are tightened or whether the sealing ring is leaking; replace if necessary, Fuel Pump (FP) unit, fuel gauge sender and suction jet pumps, removing and installing.

- Repeat function test.

If malfunction persists:

- Remove EVAP canister and check for cracks and leaks, replace if necessary.

- Check lines and hoses between EVAP canister and fuel filler tube or Evaporative Emission (EVAP) Canister Purge Regulator Valve 1 and 2 for proper seal.

- Check hoses and hose clamps for secure seating.

- Repeat function test.

If malfunction is no longer present:

Final Procedures

After the repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to --> [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 09.

2. If necessary, erase the DTC memory. Refer to --> [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09.

3. If the DTC memory was erased, generate readiness code. Refer to --> [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.