Manufacturer Code Charts: 3082

[8] Differential pressure sensor Diesel particulate filter Bank 2: Measured value implausible

Test 1: Check component B28/8 (Pressure differential sensor (DPF)).

1. Check component B28/8 (Pressure differential sensor (DPF)).
Check actual value B28/8 (Pressure differential sensor (DPF)).
Test prerequisite

- Ignition ON
- The air extractor system may not be connected to the exhaust system during the test.
Status of the relevant actual values:
- Coolant temperature:Warning! Communication with ECU required.

- Differential pressure Signal voltage:Warning! Communication with ECU required.
Specified value at coolant temperature between 10 °C and 85 °C

- Differential pressure Signal voltage464...682 mV
Specified value at coolant temperature < 10 °C or > 85 °C

- Differential pressure Signal voltage428...718 mV
Question

- Is the actual value o.k.?


YES
The actual value is okay.Figure legend

- B28/8 (Pressure differential sensor (DPF))
Further procedure

- Test wiring and plug connections between control module N3/9 (CDI control unit) and B28/8 (Pressure differential sensor (DPF)) for Loose contact, repair or replace if necessary.
End of test







NO
Check power supply of component B28/8 (Pressure differential sensor (DPF)).
Figure legend

- B28/8 (Pressure differential sensor (DPF))
Special tool

- Adapter cable611 589 03 63 00
Test prerequisite

- The actual value is not o.k.
Test prerequisite

- Switch off ignition.
- Detach coupling at component B28/8 (Pressure differential sensor (DPF)).
- Connect adapter cable no. 611 589 03 63 00 to engine wiring harness B28/8 (Pressure differential sensor (DPF)).
- Measure direct voltage with multimeter between sockets (B28/8x1) 2 and (B28/8x1) 3
- Switch on ignition.
Specified value

- Voltage[4.9...5.2] V
Question

- Is the measurement value OK?







YES
Check signal lines on component B28/8 (Pressure differential sensor (DPF)).
Figure legend

- B28/8 (Pressure differential sensor (DPF))
Special tools

- Test cable 266 589 01 63 00
- Socket box 129 589 00 21 00
- Adapter cable611 589 03 63 00
Test sequence

- Switch off ignition.
- Unplug connector of control module and component.
- Connect 126-pole socket box at engine wiring harness.
- Measure resistance with multimeter between socket (F.10) 106 of the 126-pole socket box tester and socket (B28/8x1) 1
Specified value

- Resistor<1ohms
Question

- Is the measurement value OK?







YES
The measurement value is OK.Further procedure

- Check signal line of component B28/8 (Pressure differential sensor (DPF)) for short circuit to positive.
- Check signal line of component B28/8 (Pressure differential sensor (DPF)) for short circuit to ground.
- Replace component B28/8 (Pressure differential sensor (DPF)).
End of test

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

- Repair or replace faulty cable N3/9 (CDI control unit)- B28/8 (Pressure differential sensor (DPF)).
End of test

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

- Check voltage supply lines of component B28/8 (Pressure differential sensor (DPF)) as per wiring diagram.
End of test