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 ] Readiness Code.