Engine Operating Modes
NOTE: This procedure checks whether the Engine Control Module recognizes the engine operating modes: Closed Throttle, Decel, Partially Open Throttle, Enrichment and Wide Open Throttle.
Special tools, workshop equipment, testers, measuring instruments and auxiliary items required
- VAG 1551/1552 Scan Tool using VAG 1551/3 Adaptor cable
Requirements
- Throttle cable adjustment must be OK See 'Fuel Delivery and Air Induction, Throttle Cable/Linkage, Adjustments.' Adjustments
- Engine Coolant Temperature 85 °C minimum
- Display group 04, Display zone 3.
Test sequence
- Connect VAG 1551/1552 Scan Tool See 'Testing and Inspection, Procedures, Connection and Use of Test Equipment.' Scan Tool Testing and Procedures
- Start engine and let idle
- Press 0 and 1 buttons to select Address word 01: "Engine electronics"
Display will appear as shown (example only)
06A906018AB Motronic M5.9.2 HS V06 ->
Coding 00000 WSC 00000
- Press -> button.
Display will appear as shown
Rapid data transfer HELP
Select function XX
- Press 0 and 8 buttons to select Function 08: "Read measuring value block"
- Press Q button to enter input.
Display will appear as shown
Read measuring value block
Input Display group number XXX
- Press 0, 0 and 5 buttons to select "Display group 5"
- Press Q button to enter input.
Display will appear as shown (1 to 4 = Display zones)
Read measuring value block 5 ->
1 2 3 4
- Check it ECM recognizes the operating mode by observing Display zone 4
Idle mode (Closed Throttle Position)
As long as engine is idling, idle speed must be displayed
- Display: Idle
Deceleration mode
- Raise engine speed above 3000 RPM.
- Close Throttle abruptly.
As long as engine speed is above 1400 RPM; Deceleration must be displayed
- Display: Decel
NOTE: Idle speed will be recognized below 1400 RPM.
Partially Open Throttle mode
- Raise engine speed evenly.
As long as engine speed is raised evenly, Partially Open Throttle must be displayed
- Display: Part Throt
Enrichment mode
- Quickly increase engine speed.
Enrichment must be displayed briefly
- Display: Enrich
Full throttle mode (Wide Open Throttle)
- Completely depress accelerator pedal (onto Throttle stop).
Wide Open Throttle must be displayed briefly
- Display: Full Throt
NOTE: A test drive may be required to display "Full Throt"
(Observe appropriate safety precautions during road test See 'Service Precautions.') Service Precautions
- Press -> button.
Display will appear as shown
Rapid data transfer HELP
Select function XX
- Press 0 and 6 buttons to select Function 06: "End output"
- Press Q button to enter input.
If specifications not obtained
- Check DTC memory, if necessary repair any malfunctions and then erase DTC memory See 'Testing and Inspection, Procedures, How to Pull and Clear Diagnostic Trouble Codes (DTC's).' Reading Diagnostic Trouble Codes
- Check Throttle mechanism for ease of operation.
- Check Throttle Position sensor See 'Elctronic Throttle Control Module, Testing and Inspection Procedures.' Testing and Inspection
- Display the Readiness code See 'Testing and Inspection, Procedures, Other Scan Tool Functions, Displaying and Setting Readiness Code.' Testing and Inspection
If DTC memory was erased or if the ECM was disconnected from Battery +
- Set the Readiness code See 'Testing and Inspection, Procedures, Other Scan Tool Functions, Displaying and Setting Readiness Code.' Testing and Inspection