Conducting Leak Test On Fuel Tank & Tank Ventilation System
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- For vehicles without tank leak diagnosis module, go to next step. For vehicles with tank leak diagnosis module, on Diagnosis and Information System (DIS), select CONTROL UNIT FUNCTIONS for DME MOTOR ELECTRONICS ME9 control unit. Select COMPONENT ACTIVATION from FUNCTIONS column. From SUBFRAMES column, select TANK LEAK DIAGNOSIS MODULE: ACTIVATE PUMP function. Press ACTIVATE button. Tank leak diagnosis pump pressurizes the fuel tank and tank venting system for 30 seconds. If pressure is required for longer than 30 seconds, you must press the ACTIVATE button again after 30 seconds. Go to step 3.
- For vehicles without tank leak diagnosis module, pressurize through filler neck. When leak testing with a leak detector, follow manufacturer's operating instructions. Observe country-specific accident prevention and occupational safety regulations. Go to next step.
- Possible causes of tank leakage may be tank cap leaking (check tank cap pressure relief valve), tank venting lines leaking (fuel tank, carbon canister or tank venting valve), tank venting valve leaking (engine compartment), or fuel level sensor flange on tank leaking.