Incorrect Value
Incorrect value
Information
Note! The diagnostic trouble code can also be generated due to damaged AOC-unit (clutch).Check the AOC-unit for visible damages. Listen for noise.Check the oil level in the coupling (Active on Demand Coupling).
Continue - Checking components
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Checking components
- Engine idling.
Check the function of the oil pump.
Listen using a stethoscope or a screwdriver pressed to your ear. The oil pump motor shall hum and vibrate slightly.
Note! The pump motor may sound like it's running but in certain cases it only oscillates.
Is the feed pump working?
Yes - Information
No - Checking the connectors and cables
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Information
Note! The brake control module (BCM) can cause interference in the differential electronic module (DEM). Incorrect signals from Brake Control Module (BCM) may result in the Differential Electronic Module (DEM) registering an incorrect oil pressure, thus generating the diagnostic trouble code (DTC). Therefore, troubleshoot the Brake Control Module (BCM) for incorrect signals from the wheel speed sensors.
Continue - Checking the function
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Checking the function
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.
- Ignition on.
Read the oil pressure sensor signal to check the function.
At ignition on the oil pressure shall be 0.00 +/- 0.04 MPa.
- Engine idling.
For engine at idle speed the oil pressure shall be 0.38 +/- 0.04 MPa.
Is the function OK?
Yes - Checking the function
No - Replacement of temperature/pressure sensor
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Checking the connectors and cables
- Ignition off.
Check the connector between the Differential Electronic Module (DEM) and the feed pump with respect to contact resistance and oxidation.
Check the lead between the Differential Electronic Module (DEM) and the feed pump for damage.
Reinstall the connectors, components etc.
- Engine idling.
Check the function of the oil pump.
Listen using a stethoscope or a screwdriver pressed to your ear. The oil pump motor shall hum and vibrate slightly.
Note! The pump motor may sound like it's running but in certain cases it only oscillates.
Remedy as necessary.
Other information
- Signal specification, control module for four wheel drive Signal Specification, Control Module for Four Wheel Drive
- 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
Is the feed pump working?
Yes - Verification
No - Fault-tracing information
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Checking the function
Check that the AOC-unit works by test-driving the vehicle on the lift (to increase the clutch oil pressure). Read off the oil pressure during the test-drive.
Test drive the vehicle following:
Test driving on lift, automatic transmission, AW50/51 AWD Initial Inspection and Diagnostic Overview
Hint: If the AOC-unit is not working, try with replacing control module.
Repeat the test-drive.
Other information
- Signal specification, control module for four wheel drive Signal Specification, Control Module for Four Wheel Drive
- 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
Is the function OK?
Yes - Verification
No - Fault-tracing information
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Replacement of temperature/pressure sensor
- Ignition off.
Replace oil pressure sensor.
Hint: The oil pressure sensor is integrated with the oil temperature sensor and these are located together with the Differential Electronic Module (DEM). Temperature/pressure sensor is replaceable.
Check that the oil pressure sensor works after the replacement.
- Ignition on.
Read the oil pressure sensor signal to check the function.
At ignition on the oil pressure shall be 0.00 +/- 0.04 MPa.
- Engine idling.
Read the oil pressure sensor signal to check the function.
For engine at idle speed the oil pressure shall be 0.38 +/- 0.04 MPa.
Other information
- Signal specification, control module for four wheel drive Signal Specification, Control Module for Four Wheel Drive
- Temperature / pressure sensor active on demand coupling, replacing, M58, M66 AWD, AW50/51 AWD Temperature / Pressure Sensor Active On Demand Coupling, Replacing
- Differential electronic module (DEM), replacement Service and Repair
- Checking wiring and terminals Checking Wiring And Terminals
Is the function OK?
Yes - Verification
No - Checking the function
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Verification
Hint: After carrying out the repair, check that the fault has been remedied.
Test-driving is required to ensure that the malfunction has been fixed.
Test drive the vehicle following:
Test driving on lift, automatic transmission, AW50/51 AWD Initial Inspection and Diagnostic Overview
Check that the diagnostic trouble code (DTC) is not generated again after the test-drive.
Is the function OK?
Yes - Fault Found
No - 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 - Information
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