Checking the Display Screen
Checking the display screen
Fault-tracing information
Fault causes which will stop the display working:
- Open-circuit in the signal cable between the display and the multimedia module (MMM)
- No power supply to the display screen
- The display screen is not working
- Damaged multimedia module (MMM)
- The MOST network is not working
- The relay for the infotainment system (positioned on the central electronic module (CEM)) is not powered.
Hint: The display screen will not deploy in the event of a fault in the MOST network. If the display screen is deployed and the data on the screen does not update or the screen suddenly retracts, the MOST network may not be working. Check that the MOST network is working.
Continue - Symptom information
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Symptom information
- Ignition on.
Activate the multimedia module (MMM) using the navigation buttons or the remote control so that the display screen deploys and retracts.
Does the screen deploy and retract?
Yes - FAULT FOUND
No - Checking the cable
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Checking the cable
- Ignition off
- Disconnect the 5-pin connector from the display screen
- Ignition on.
Checking the cable
Check the display screen cable terminals. Check for oxidation and loose connections.
Check the cable terminals in the female and male sections of the connector. The cable terminals must not be damaged or pressed back.
Check the voltage at the 5-pin connector for the screen. The voltage should be 12 V.
Take readings between:
- terminals #1 and #5
- terminals #2 and #4
- terminals #3 and #4.
If the voltage is not 12 V, check terminals #1, #2 and #3 in the 5-pin connector for the screen. Check for a short-circuit to ground. Check for an open-circuit.
If the voltage is not 12 V, check terminals #4 and #5 in the 5-pin connector for the screen. Check for a short-circuit to supply voltage. Check for an open-circuit.
Other information
- Signal specification Signal Description, Multimedia Module (MMM)
- Control module information and entertainment Control Module Information and Entertainment
- For information about signals, see: Display navigation and entertainment Service and Repair
- Checking wiring and terminals Checking Wiring and Terminals.
Was the fault found?
Yes - Verification
No - Checking the cable
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Checking the cable
- Ignition off
- Disconnect the 10-pin connector from the display screen and multimedia module (MMM).
Checking the cable
Check the cable terminals between the display screen and multimedia module (MMM). Check for oxidation. Check for loose connections.
Check the cable terminals in the female and male sections of the connector. The cable terminals must not be damaged or pressed back.
Check the signal cable between display screen terminal #7 (10-pin connector) and multimedia module (MMM) terminal #B7 (#7). Check for a short-circuit to supply voltage. Check for an open-circuit.
Check the signal cable between display screen terminal #4 (10-pin connector) and multimedia module (MMM) terminal #B4 (#4). Check for a short-circuit to supply voltage. Check for a short-circuit to ground. Check for an open-circuit.
If no fault is found, replace the display screen.
Remedy as necessary.
Other information
- Connecting the breakout box Connecting the Breakout Box, Multimedia Module (MMM)
- Signal specification Signal Description, Multimedia Module (MMM)
- Display navigation and entertainment Service and Repair
- Control module information and entertainment Control Module Information and Entertainment
- Checking wiring and terminals Checking Wiring and Terminals
Continue - Verification
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Verification
Verification
Hint: After carrying out the repair, check that the fault has been remedied.
- Ignition off
- Reinstall the connectors, components etc.
- Ignition on.
Check that the screen deploys when the ignition is switched on, when activated using the remote control or when using the steering wheel buttons for navigation.
Ensure that the image and the colors of the image are good.
Does the display function?
Yes - VERIFIED
No - VERIFICATION FAILED
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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 - Exit Fault-Tracing
No - Attempt New Test
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Attempt New Test - Fault-tracing information
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