Faulty Signal

Faulty signal

Checking the function

Caution! Carry out the test with the vehicle raised so that all four wheels can rotate freely with the mounting at the ends of the control arms to prevent damage to the drive shafts.

Warning! Ensure that the vehicle is safely raised. Check that no objects are caught in the tire treads.

Note! If the vehicle is equipped with TRACS (traction control system) or Traction Control (DSTC (Dynamic stability and traction control), STC (Stability and traction control)) the function must be deactivated. This is carried out by removing the fuse for the brake system pump motor in the engine compartment relay and fusebox. Note that diagnostic trouble codes (DTCs) will be stored in the brake control module (BCM). These must be erased before returning the vehicle to the customer.

- Engine idling
- Read off the oil pressure.
Check that the function of the oil pressure sensor is OK. Run the engine with the vehicle on the lift to increase the clutch oil pressure. Read off the pressure during the test drive. Check that the pressure has been updated.

Hint: The oil pressure sensor has a measurement range of 0 to 4 Mpa.

Check the connector between the differential electronic module (DEM) and the oil pressure sensor. Check for contact resistance and oxidation.
Also check the clutch for leakage.
Remedy as necessary.

Other information:
- For further information about the fuses and relays, see the Wiring Diagram
- Signal specification, differential electronic module (DEM) , M58, AW50/51 AWD Signal Specification, Differential Electronic Module (DEM)
- Temperature / pressure sensor active on demand coupling, replacing, M58, M66 AWD, AW50/51 AWD Temperature / Pressure Sensor Active On Demand Coupling, Replacing
- Active on Demand Coupling (AOC), replacing Service and Repair
- Differential electronic module (DEM), replacement Service and Repair
- Checking wiring and terminals Checking Wiring And Terminals

Continue - Verification

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Verification

Verification

Verification

Hint: After carrying out the repair, check that the fault has been remedied.

Is the function OK?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFIED - Fault Found

VERIFICATION FAILED - Fault-tracing information

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Fault-tracing information

Information

Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.

Do you want to exit fault-tracing?

Yes - FAULT-TRACING FAILED

No - Attempt New Test

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FAULT-TRACING FAILED - FAULT-TRACING FAILED

Attempt New Test - Checking the function

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Checking pressure and temperature sensor

Checking pressure and temperature sensor

Checking pressure and temperature sensor

Note! Reading out of oil pressure can take place first after the diagnostic trouble code (DTC) has been deleted. Therefore frozen values should be printed and saved before deleting takes place.

1. Test of pressure sensor.
- Ignition on.
- Press the VCT2000 symbol.

Hint: Correct pressure shall be 0.00 +/- 0.08 MPa.

- Engine idling
- Press the VCT2000 symbol.

Hint: Correct pressure shall be 0.38 +/- 0.08 MPa.

1. Test of temperature sensor.
- Ignition on.
- Press the VCT2000 symbol.

Hint: Normal value for ambient temperature when the vehicle is cold and (+20 to +50 °C) when the vehicle is driven.

If wrong value is read out, then diagnostic trouble code shall be erased and the sensor changed. After changing sensor, repeat the test procedure again.

Note! There are two types of sensors, an 80 bar and a 40 bar. Differential electronic module (DEM) has hardware number 30759701, 30785483, 30759682, 30783198, 30735844, or 30783018, an 80 bar pressure sensor shall be installed. If Differential electronic module (DEM) has another hardware number than above, a 40 bar sensor shall be installed.

Hint: For reading out of hardware number, see VIDA/DIAGNOSTICS/NETWORK/DEM.

Other information
- Temperature / pressure sensor active on demand coupling, replacing, M58, M66 AWD, AW50/51 AWD Temperature / Pressure Sensor Active On Demand Coupling, Replacing

Has the fault been remedied?

Yes - DONE

No - No Fault Found

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DONE - DONE

No Fault Found - Checking the function

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