Engine Operating Mode Check

Engine Operating Mode, Checking

NOTE: Checks whether engine control module recognizes the engine operating modes idling, overrun, part throttle, enrichment, full throttle.

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

Test conditions
- Coolant temperature must be at least 80°C, See display group 04, display zone 3.

Test sequence
- Connect V.A.G 1551 scan tool ((VAG1552). Start engine and select "Address word" 01 of engine control module. When doing this the engine must be running at idling speed. [1][2]Reading and Clearing Diagnostic Trouble Codes

Indicated on display:

Rapid data transfer HELP
Select function XX

- Press keys 0 and 8 for the function "Read measuring value block" and confirm entry with Q key.

Indicated on display:

Read measuring value block
Input display group number XXX

- Press keys 0, 0 and 5 for "Display group number 5" and confirm entry with Q key.

Indicated on display: (1 to 4 = Display zones)

Read measuring value block 5 ->
1 2 3 4

- Check whether the control module recognizes the operating mode (display zone 4):

Idling:
As long as the engine is running at idling speed idling must be displayed
Display: Idling

Overrun mode:
- Increase engine speed to above 3000 RPM.
- Quickly release accelerator pedal.
As long as the engine speed is above 1400 RPM overrun must be displayed
Display: Overrun

NOTE: Below 1400 RPM idling speed will be recognized.

Part throttle:
- Rev up evenly.
As long as the engine is being revved up evenly, part throttle must be displayed
Display: Part throttle.

Enrichment and full throttle:
- Depress accelerator pedal completely (throttle burst)
Enrichment and then full throttle should be displayed briefly
Display: Enrich. and then full throttle.

NOTE: A test drive may have to be performed to show "Full throttle" in display.

Observe the valid safety precautions when carrying out a road test.

- Press -> key.
- Press keys 0 and 6 for the "End data transfer" function and confirm input with the Q key.

If the specifications are not attained:
- Check throttle valve control module Testing and Inspection
- Check DTC memory, if necessary, repair any faults and then erase DTC memory
Reading Diagnostic Trouble Codes
Clearing Diagnostic Trouble Codes