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Home >> Volkswagen >> 2017 >> Jetta SEL >> Repair and Diagnosis >> Engine Performance >> Ignition System >> Engine System (Diagnostics & General Information - CPRA - 2 Of 2) >> St Generic Scan Tool >> Diagnosis And Testing >> Diagnostic Modes 01 - 09 >> Diagnostic Mode 08 - Request Control Of On- Board System, Test Or Component >> Function test
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Function test

NOTE:

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

- - Connect the scan tool.

- - Start the engine and run at idle for at least 15 minutes.

- - Select "Mode 8: Tank Leak Test".

- - Select "Test- ID 01: Tank Leak Test".

- - Check the specified value of the tank leak test at idle.

- - The following will be displayed on the scan tool screen:

Tank leak test Specified value
  • Test function active
  • Test function is being initiated, please wait
  • Test off
  • Test aborted
Test OK

- - Switch the ignition off.

If the specified result is obtained: 

System OK.

If the specified result is Not obtained: 

- - Repeat the tank leak test, switch the ignition off and start the engine again and let run for 15 minutes at idle.

- - Switch the ignition off.

If the specified result is again Not obtained: 

- - A leak may be present. Refer to EVAP SYSTEM, CHECKING FOR LEAKS .