Manufacturer Code Charts: 2937
[1] Irregular running value of cylinder 4: Rough running is too severe.
Test 1: Check system 'Misfiring'.
1. Check system 'Misfiring'.
Test 1.1: Check low-pressure fuel circuit.
Test 1.2: Check fuel type: Gasoline. ?
Test 1.3: Check injectors.
Test 1.4: Check components of high pressure control circuit.
Test 1.5: Check synchronization between crankshaft and camshaft.
1.1. Check low-pressure fuel circuit.
Warning!Risk of explosion, poisoning and injury!Fuels are highly inflammable and toxic if inhaled. Fuels may cause skin damage. fuel vapors are explosive, invisible and spread out at floor level, they are toxic if inhaled and produce giddiness and an anaesthetizing effect.Rules of conduct and protective measures
- Wear suitable protective clothing.
- Pay attention to national safety precautions and regulations.
- No fire, sparks, naked flames and smoking.
- Ensure the work place is adequately ventilated.
- Never drain or pour in fuels over assembly pits.
- Store drained fuel in a suitable and sealed vessel.
- Immediately eliminate any fuel which has flowed out.
First-aid measures
- Clean moistened skin with water and soap.
- Change moistened clothing as quickly as possible.
- If fuel gets into your eyes, rinse out your eyes immediately with water and contact a doctor if necessary.
Please check the fault freeze frame data.
Question:How high was the tank fill level when the fault occurred?Question:Read fault memory once again.
YES
1.1. No further information available.
NO
Question:Was the tank fill level > 10 l ?
YES
Test prerequisites:Tank fill level is > 10 l.Type of fuel (Diesel)The low pressure fuel circuit has no external leaks.Continue with button F2
Test pressure in fuel low pressure circuit.
Figure legend
- 043Pressure measuring device0-10 bar(103 589 00 21 01)
- aT-piece for pressure test upstream of fuel filter(A 620 990 03 70)
- bT-piece for pressure test downstream of fuel filter(A 673 990 03 70)
- Shop-make test lines as shown in picture.
- This test can also be carried out alternatively with a commercially available pressure-vacuum tester with an appropriate test connector.
- Hydraulic clutch: see Workshop Equipment Manual WH58.30-Z-1054-13A
Test fuel pressure at fuel filter inlet.
Special tool
- 043Pressure measuring device0-10 bar(103 589 00 21 01)
Figure legend
- 043Pressure measuring device
- 70/1Inlet at fuel filter
IMPORTANT NOTE
- Kinked or clogged fuel lines may result in fuel pressures of up to 8 bar.
- Fabricate your own hose lines with a diameter of 8 mm and 10 mm.
Test sequence
- Switch off ignition.
- Await run-on time.
- Connect test pressure gauge.[See fig.]
- Start and run engine at idle speed for approx. 15 s.
Continue with button F2
Warning!Communication with ECU required.
NO
End of test
1.2. Check fuel type: Gasoline. ?
1.2. No further information available.
1.3. Check injectors.
Test 1.3.1: Test of compression
Test 1.3.2: Quantity correction values of smooth-running control
Test 1.3.3: Check internal resistance of component Y76 (Fuel injectors).
Test 1.3.4: Test cables to component Y76 (Fuel injectors) for open circuit.
Test 1.3.5: Test current consumption of component Y76 (Fuel injectors).
1.3.1. Test of compression
Test of compression
Test prerequisite
- Ignition ON
- Engine not running
NOTE RE Test of compression
- As of an rpm difference greater than 7 1/min between the lowest and the highest value, a mechanical compression test and cylinder leak test must be performed on all cylinders to locate the fault.
Note:Turn ignition key to position 'Engine start' when prompted by DAS and hold until the progress bar has reached the end.On KEYLESS GO vehicles, press and hold the start/stop button and brake pedal when prompted by DAS until the progress bar has reached the end.Continue to test with button F2
Warning!Communication with ECU required.
1.3.2. Quantity correction values of smooth-running control
Test 1.3.2.1: Test prerequisite : Test of compression
Test 1.3.2.2: Test prerequisite : The injector injection quantity adjustment values stored in the control unit match the imprint on the injectors.
Test 1.3.2.3: Quantity correction values of smooth-running control
1.3.2.1. Test prerequisite : Test of compression
Test of compression
Test prerequisite
- Ignition ON
- Engine not running
NOTE RE Test of compression
- As of an rpm difference greater than 7 1/min between the lowest and the highest value, a mechanical compression test and cylinder leak test must be performed on all cylinders to locate the fault.
Note:Turn ignition key to position 'Engine start' when prompted by DAS and hold until the progress bar has reached the end.On KEYLESS GO vehicles, press and hold the start/stop button and brake pedal when prompted by DAS until the progress bar has reached the end.Continue to test with button F2
Warning!Communication with ECU required.
1.3.2.2. Test prerequisite : The injector injection quantity adjustment values stored in the control unit match the imprint on the injectors.
Adjustment of injector injection quantities
Figure legend/figure1
- Y76 (Fuel injectors)
Figure legend/figure2
- 1-6Arrangement of cylinders
Important notes
- The adjustment of injector injection quantities must be performed when replacing injectors.
- After replacing one or several injectors, the corresponding adjustment values of the injectors replaced must be recorded in the control module for the specific cylinder.
- The 7 digits marked with a circle represent the adjustment value.
- The values of the zero quantity calibration and the quantity mean value adaptation are automatically reset during the injector injection quantity adjustment.
- The engine may temporarily run more roughly after the injector injection quantity adjustment because the learned values are reset.
Communication with ECU required
1.3.2.3. Quantity correction values of smooth-running control
Test prerequisite
- Move transmission into Neutral position.
- Operate parking brake.
- Engine at idle
- Actuation: Test of compression OK
Important notes
- In the case of complaints related to a cold start or to the warm-up phase, do not bring the engine to operating temperature, but proceed as appropriate for the complaint.
- An injector injection quantity adjustment must be performed after every injector replacement.(Control unit adaptations/Adjustment of injector injection quantities)
Status of relevant actual value:
- Transmission neutral contact:Warning!
Communication with ECU required
1.3.3. Check internal resistance of component Y76 (Fuel injectors).
Help text:Specify the injector to be tested.1...6
1.3.3. No further information available.
1.3.4. Test cables to component Y76 (Fuel injectors) for open circuit.
Help text:Specify the injector to be tested.1...6
1.3.4. No further information available.
1.3.5. Test current consumption of component Y76 (Fuel injectors).
Figure legend
- Adapter cable
- 065Current clamp
- Y76 (Fuel injectors)
Special tool
- Adapter cable220 589 00 99 35
Test sequence
- Switch off ignition.
- Detach coupling at component Y76 (Fuel injectors).
- Connect adapter cable between component Y76 (Fuel injectors) and engine wiring harness.
- Connect current clamp (see illustration).
- Start engine.
Specified value
- Compare the oscillogram with the characteristics specified for component Y76 (Fuel injectors).
Note
- Measuring system:Communication with ECU required
1.4. Check components of high pressure control circuit.
Check components of high pressure control circuit.
Important notes
- This test is used to check the entire high pressure control circuit.
- In the case of complaints related to a cold start or to the warm-up phase, do not bring the engine to operating temperature, but proceed as appropriate for the complaint.
- If no faulty components are identified during the test, do not replace any components.
Test prerequisites
- Compression test in menu 'Actuations' was carried out.
- The pressure of the fuel low pressure system is OK.
Communication with ECU required
1.5. Check synchronization between crankshaft and camshaft.
Test 1.5.1: Check component B6/1 (Camshaft Hall sensor).
Test 1.5.2: Check component B70 (Crankshaft Hall sensor).
Test 1.5.3: Check synchronization between crankshaft and camshaft.
1.5.1. Check component B6/1 (Camshaft Hall sensor).
Test 1.5.1.1: Check power supply of component B6/1 (Camshaft Hall sensor).
Test 1.5.1.2: Signal Check component B6/1 (Camshaft Hall sensor).
1.5.1.1. Check power supply of component B6/1 (Camshaft Hall sensor).
Figure legend
- B6/1 (Camshaft Hall sensor)
- Plug connection B6/1x1
Commercially available tools
- Measuring system Adapter cable Pal 029
Test sequence
- Switch off ignition.
- Detach coupling at component B6/1 (Camshaft Hall sensor).
- Connect adapter cable to engine wiring harness.
- Measure direct voltage with multimeter between sockets (B6/1x1) 1 and (B6/1x1) 3
- Switch on ignition.
Specified value
- Voltage[4.9...5.2] V
Question
- Is the measurement value OK?
YES
The measurement value is OK.Possible cause and remedy
- Signal Check component B6/1 (Camshaft Hall sensor).
End of test
NO
The measurement value is not OK.Possible cause and remedy
- Check lines from control module N3/9 (CDI control unit) to component B6/1 (Camshaft Hall sensor) against wiring diagram.
End of test
1.5.1.2. Signal Check component B6/1 (Camshaft Hall sensor).
Figure legend
- B6/1 (Camshaft Hall sensor)
Commercially available tools
- Measuring system Adapter cable Pal 029
Test sequence
- Switch off ignition.
- Connect adapter cable to component B6/1 (Camshaft Hall sensor).
- Connect STAR DIAGNOSIS with special tool.
- Observe oscilloscope pattern between A4 Blue Socket and A7 Green Socket
- Operate starter for the duration of at least 10.
Specified value
- Compare the oscillogram with the characteristics specified for component B6/1 (Camshaft Hall sensor).
Communication with ECU required
1.5.2. Check component B70 (Crankshaft Hall sensor).
Test 1.5.2.1: Test signal voltage of component B70 (Hall-Geber Kurbelwelle).
Test 1.5.2.2: Check power supply of component B70 (Hall-Geber Kurbelwelle).
1.5.2.1. Test signal voltage of component B70 (Hall-Geber Kurbelwelle).
Test 1.5.2.1.1: The engine does not start.
Test 1.5.2.1.2: Engine running
1.5.2.1.1. The engine does not start.
Settings
- Trigger level: 50 %
- Time range: 5 ms
Test sequence
- Switch off ignition.
- Connect socket box (126-pin) to component N3/9 (CDI control unit).
- Observe oscilloscope pattern between sockets (M.31) 31(A7) and (M.77) 77(A4) of the 126-pole socket box tester.
- Start engine.
Specified value
- Measuring system
Warning!The rising signal edge in the gap (see arrow) may vary.Note
- Measuring system:Communication with ECU required
1.5.2.1.2. Engine running
Settings
- Trigger level: 50 %
- Time range: 5 ms
Test sequence
- Switch off ignition.
- Connect socket box (126-pin) to component N3/9 (CDI control unit).
- Observe oscilloscope pattern between sockets (M.31) 31(A7) and (M.77) 77(A4) of the 126-pole socket box tester.
- Operate engine at idling speed.
Specified value
- Measuring system
Warning!The rising signal edge in the gap (see arrow) may vary.Note
- Measuring system:Communication with ECU required
1.5.2.2. Check power supply of component B70 (Hall-Geber Kurbelwelle).
Figure legend
- B70 (Crankshaft Hall sensor)
Test sequence
- Switch off ignition.
- Unplug 3-pin connector from component B70 (Crankshaft Hall sensor).
- Measure direct voltage with multimeter between sockets (B70x1) 1 and (B70x1) 3
- Switch on ignition.
Specified value
- Voltage[4.8...5.3] V
Question
- Is the measurement value OK?
YES
The measurement value is OK.Possible cause and remedy
- Test signal cable to component B70 (Crankshaft Hall sensor).
- The teeth on the increment wheel may be bent.
- Engine overevving has occurred.
- B70 (Crankshaft Hall sensor)
End of test
NO
The measurement value is not OK.Possible cause and remedy
- Lines to component B70 (Crankshaft Hall sensor)
End of test
1.5.3. Check synchronization between crankshaft and camshaft.
Special tools
- Test cable 266 589 01 63 00
- Socket box 129 589 00 21 00
Test sequence
- Switch off ignition.
- Connect 126-pole socket box between engine wiring harness and control module N3/9 (CDI control unit).
- Connect measuring system.
- Enter the settings as shown in the right-hand diagram.
- A7Observe oscilloscope pattern between ground and socket (M.77) 77 of the 126-pole socket box tester.A4
- A7Observe oscilloscope pattern between ground and socket (M.33) 33 of the 126-pole socket box tester.A1
- Start engine.
Communication with ECU required
