Engine Operating Conditions, Checking
NOTE: The check establishes whether Motronic Engine Control Module (ECM) -J220- recognizes the engine operating modes idling, overrun, part throttle, full throttle and enrichment.
Special tools, workshop equipment, testers, measuring instruments and auxiliary items required
- VAG 1551 Scan tool (or VAG 1552) with VAG 1551/3 adapter cable
NOTE: All functions which could previously be performed with VAG 1551/1552 can also be performed with the VAS 5051.
Test prerequisites
- Engine Coolant Temperature (ECT) must be at least 85 degrees C, See display group 1, display zone 2
Test sequence
- Connect VAG 1551 Scan tool (or VAG 1552) and select engine electronics control module with the "Address word" 01. When doing this the engine must be running at idle speed: ((VAG 1551 and Motronic Engine Control Module (ECM) -J220-, connecting and selecting). [1][2][3]Connecting VAG 1551 Scan Tool
Indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -8- for function "Read measured value (data) block" and confirm entry with -Q- button.
Indicated on display:
Read measured value block
Input display group number XXX
- Press buttons -0-, -0- and -5- for "Display group number 5" and confirm entry with -Q- button.
Indicated on display: (1...4 = display zones)
Read measured value block 5
1 2 3 4
- Check whether the control module recognizes the operating conditions (display zone 4):
- Idling:
Idling must be displayed as long as the engine is running at idle speed Display: Idling
- Part throttle:
- Rev up evenly.
As long as the engine is being revved up evenly, part throttle must be displayed
Display: Part throt.
- Enrichment:
- Floor accelerator pedal (onto throttle valve limit stop).
Acceleration enrichment must be displayed briefly
Display: Enrich.
- Overrun mode:
- Increase engine speed to above 3000 rpm.
- Close throttle valve abruptly.
Display: Overrun
NOTE: A road test may have to be performed to show "Overrun" in display.
Observe the valid safety precautions when carrying out a road test. Refer to "Fuel Delivery and Air Induction/Service Precautions", [1][2]Technician Safety Information
- Full throttle:
- Floor accelerator pedal (onto throttle valve limit stop).
Full load must be displayed briefly
Display: Full load
NOTE: A road test may have to be performed to show "Full load" in display.
Observe the valid safety precautions when carrying out a road test. Refer to "Fuel Delivery and Air Induction/Service Precautions", [1][2]Technician Safety Information
- Press the -> button.
- Press buttons -0- and -6- for function "End output" and confirm entry with the -Q- button.
If the specifications are not obtained:
- Check DTC memory, repair malfunctions if necessary and then erase DTC memory. Reading Diagnostic Trouble Codes
- Check Throttle Valve Control Module -J338- Refer under "Powertrain Management/Computers and Control Systems/Electronic Throttle Control Module". Testing and Inspection
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery positive (B+), the readiness code must be generated again. Monitors, Trips, Drive Cycles and Readiness Codes Monitors, Trips, Drive Cycles and Readiness Codes