[1] Check component Y27/9 (Left EGR positioner).: Short circuit to positive

[1] Check component Y27/9 (Left EGR positioner).: Short circuit to positive

Test 1: Check component Y27/9 (Left EGR positioner).

1. Check component Y27/9 (Left EGR positioner).

Test 1.1: Inspect charge air system for leaks.

Test 1.2: Check actual value Y27/9 (Left EGR positioner).

Test 1.3: Actuation of component Y27/9 (Left EGR positioner)

Test 1.4: Check component Y27/9 (Left EGR positioner).

1.1. Inspect charge air system for leaks.
Inspect charge air system for leaks.
Important notes

- The following test sequence has changed.
- Follow the test procedure precisely!
- The test must be performed with the engine oil cap removed.
Communication with ECU required

1.2. Check actual value Y27/9 (Left EGR positioner).
Test prerequisite

- Engine at idle
- Briefly blip throttle.
Status of relevant actual value:
- Exhaust gas recirculation positioner:Warning! Communication with ECU required.
Specified value

- Engine at idle
- On/off ratio:( >35 ) %
Question

- Is the actual value o.k.?


YES
The actual value is okay.If faults with high fault frequency counters or customer complaints are stored, inspect cables and plug connections between control module N3/9 (CDI control unit) and component Y27/9 (Left EGR positioner) for loose contact and corrosion.End of test

NO
The actual value is not o.k.Possible cause and remedy

- Check component Y27/9 (Left EGR positioner) by means of actuation.
End of test

1.3. Actuation of component Y27/9 (Left EGR positioner)
Warning!Communication with ECU required.


1.4. Check component Y27/9 (Left EGR positioner).

Test 1.4.1: Check power supply of component Y27/9 (Left EGR positioner).

1.4.1. Check power supply of component Y27/9 (Left EGR positioner).
Test prerequisite

- The actuation was not okay.
Figure legend

- Y27/9x1Plug connection Exhaust gas recirculation positionerLeft
Test prerequisite

- Switch off ignition.
- Detach coupling at component Y27/9 (Left EGR positioner).
- Measure direct voltage with multimeter between sockets (Y27/9x1) 3 and (Y27/9x1) 2
- Switch on ignition.
Specified value

- Voltage[11...14V]
Question

- Is the measurement value OK?







YES

Test 1.4.1.1: Test signal cable to component N3/9 (CDI control unit).

1.4.1.1. Test signal cable to component N3/9 (CDI control unit).
Special tools

- Test cable 271 589 00 63 00
- Socket box 129 589 00 21 00
Test sequence

- Switch off ignition.
- Connect 126-pole socket box at engine wiring harness.
- Measure resistance with multimeter between socket (1.90) 90 of the 126-pole socket box tester and (Y27/9) 1
Specified value

- Resistance <1 Ohm?
Question

- Is the measurement value OK?


YES
The measurement value is OK.If faults with high fault frequency counters or customer complaints are stored, inspect cables and plug connections between control module N3/9 (CDI control unit) and component Y27/9 (Left EGR positioner) for loose contact and corrosion.Replace component Y27/9 (Left EGR positioner).End of test

NO
The measurement value is not OK.Possible cause and remedy

- Test cables and connections, rectify any short circuit.
End of test

NO
The measurement value is not OK.Possible cause and remedy

- Test wiring of voltage supply between component Y27/9 (Left EGR positioner) and component N3/9 (CDI control unit).
End of test