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Ignition System: Testing and Inspection




Misfire Recognition

Special tools and equipment
- V.A.G 1551 scan tool (or VAG 1552 mobile scan tool) with VAG 1551/3B cable

Test sequence
- Connect V.A.G 1551 scan tool (VAG 1552). Start engine and select the Engine Control Module (ECM) using address word 01. (connecting scan tool and selecting ECM). Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/Connecting VAG 1551 Scan Tool", Testing and Inspection

Indicated on display:


Rapid data transfer HELP
Select function XX



- Press buttons -0- and -8- to select "Read measuring value block" function 08. Press -Q- button to confirm input.

Indicated on display:


Read measuring value block
Enter display group number XXX



- Press buttons -0-, -1- and -4- to select "display group number 14" and then press -Q- button to confirm input.

Indicated on display: (1 to 4 - display fields)


Read measuring value block 14 ->
1 2 3 4



- Check the total number of misfires in display field 3: Specification: 0 to 5
- Check the status of misfire recognition in display field 4: Specification: activated

If specified values are obtained:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06. Press -Q- button to confirm input.
- Switch ignition off.

If specified values are not obtained:
- Check spark plugs, Parts of ignition, removing and installing.
- Check ignition coils with power output stage. Testing and Inspection
- Check fuel injector. Refer to "Fuel Injectors, Checking", Testing and Inspection