Diagnostic mode 8: Tank leak test
NOTE:
This diagnostic mode can only be selected with Module number 10 - Engine Electronics.
Function
This diagnostic mode checks the fuel system for leaks.
NOTE:
- The Evaporative Emission (EVAP) Canister Purge Regulator Valve(s) and Leak Detection Pump (LDP) -V144- seal the tank system.
- Pressure (max. 70 mbar) can be applied to the fuel system via the test connection (in engine compartment, right) and via engine leak detection spray (e.g.: G 001 800 A1) leaks can be detected.
Test requirements
- There must not be any DTCs stored in DTC memory. Refer to Diagnostic mode 3: Check DTC Memory
- Coolant temperature must be 80 to 110 ° C. Refer to Diagnostic mode 1: Check measured values
- Intake air temperature must not be above the maximum of 60 ° C. Refer to Diagnostic mode 1: Check measured values
Function test
- Connect diagnostic tester. Refer to Diagnostic tester, connecting
- Start engine and let run 15 minutes at idle.
- Under address word 33, select "Diagnostic mode 8: Tank leak test".
- Select measuring value "Test-ID 01: Tank leak test".
- Check specified value of tank leak test at idle.
Evaluation test-ID 01: Tank leak test
| Tank leak test |
Specified value: | |||||
Test function:
|
Test function active | |||||
NOTE:
- 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:
- EVAP canister system, checking for proper seal. Refer to Evaporative Emission (EVAP) canister system, checking for proper seal .
- Check Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-. Refer to Evaporative Emission (EVAP) canister purge regulator valve 1, checking .
- Leak Detection Pump (LDP) -V144-, checking. Refer to Leak Detection Pump (LDP), checking .
Vehicles with engine code BJS
- Check Evaporative Emission (EVAP) Canister Purge Solenoid Valve -N115-. Refer to Evaporative Emission (EVAP) canister purge solenoid valve 2 (vehicles with engine code BJS), checking .
Continuation for all vehicles
- Erase DTC memory of Engine Control Module (ECM). Refer to Diagnostic mode 4: Reset/erase diagnostic data
- Generate readiness code. Refer to Readiness code, generating