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Diagnostic Mode 8: Tank Leak Test



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 -N80-, Evaporative Emission (EVAP) Canister Purge Solenoid Valve -N115- and Leak detection pump (LDP) -V144- seal the fuel system.
- Using 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.
Coolant temperature must be 80 to 110°C.
Intake air temperature must not be above the maximum of 60°C.

Function test
- Connect diagnostic tester.
- Start engine and let run 15 minutes at idle.Under address word 33, select "Diagnostic mode 8: Tank leak test".
- Measuring value "Test-ID 01: select Tank leak test".
- Check specified value of tank leak test at idle.

Evaluation test-ID 01: Tank leak test






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.
- Check Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-.
- Check Evaporative Emission (EVAP) Canister Purge Solenoid Valve -N115-.
- Leak Detection Pump (LDP) -V144-.
- Erase DTC memory of Engine Control Module (ECM).
- Generate readiness code.