NOTE: Visually check for any of the following conditions and correct any problems found before performing any MOST network checks.
- Any sharp bends in fiber optic wiring harnesses (perform this test before moving any modules or connectors)
- Incorrect docking of any optical connectors
- Improper mating of any electrical connectors
- Damaged fiber optic wiring harness (abrasion, abrasive wear, creases, cuts, tears, etc.)
- Incorrect assembly of the optical network
NOTE: Unless otherwise noted, make sure the ignition is on when performing MOST network tests ('ON')
Pinpoint test A: MOST network checks
A1: HLDF display test
Check the HLDF display. Does the HLDF display show a flashing Land Rover logo or a blank screen?
Yes - GO to A2.
No - No fault has occurred at the checkpoint. There may be a parameter error in the vehicle configuration file. Check the modules in the MOST network for the relevant DTCs and refer to the relevant DTC index.
A2: RD1 checkpoint link check
Check the RD1 test point link in the auxiliary power junction box (AJB) for possible disconnection or interruption of the electrical circuit. Reference point link RD1 in auxiliary electrical box (AJB) disconnected or there is an open circuit.
Yes - Repair the problem and recheck the condition of the vehicle. No - GO to A3.
A3: Initiating diagnostics with a checkpoint (RBD) and reading DTCs
- Check for the presence of the RD1 checkpoint link in the AJB.
- Make sure the remote key is in the holder.
- Turn the vehicle ignition from the 'OFF' position to the 'ON' position.
- Clear all DTCs.
- Remove the RD1 breakpoint link from the AJB, wait at least ten seconds, and reattach the RD1 loop break link to the AJB.
- Wait at least 30 seconds for the RBD to initiate and complete the operation.
- Read all DTCs.
Yes - GO to A4.
No - Check the HLDF for additional DTCs and refer to the appropriate DTC Index.
A4: Checking for a fault on pin 2 of the intermediate connector C23T
Disconnect the intermediate connector C23T of the MOST network. Can you see a bright red light on pin 2 of the MOST C23T intermediate connector?
Yes - GO to A5.
No - GO to A6.
A5: Check for a fault in the first half of the MOST network
- Connect an optical bus tester (OBT) to the intermediate connector C23T using the supplied connecting cable.
- Enable OBT ('ON') and select 2+0 mode.
- Select visible LED mode.
Yes - Malfunction in the second half of the MOST network. Disconnect the OBT and reconnect the intermediate connector. GO to A13.
No - Disconnect the OBT from the intermediate connector C23T and connect the supplied optical LINK. GO to A10.
A6: Infotainment Module Fault Check
Disconnect the MOST network connector C2ME05B on the infotainment module. Can you see a bright red light on pin 2 of connector C2ME05B, from the side of the module?
Yes - Is HLDF installed on the vehicle? GO to A7. If HLDF is not installed, the fiber optic cable between C2ME05B pin 2 and C23T pin 2 is faulty; repair the problem and recheck the vehicle.
No - Install a new infotainment module and recheck the vehicle.
A7: Checking for a failure in the fiber optic cable to the HLDF
- Reconnect the MOST network connector C2ME05B on the infotainment module.
- Disconnect the MOST network connector C2MN08C on the HLDF.
Yes - GO to A8.
No - Faulty fiber optic wiring harness between C2ME05B pin 2 and C2MN08C pin 1; repair the problem and recheck the vehicle.
A8: Checking for a failure of the fiber optic cable coming from the HLDF
- Connect the OBT to the MOST network connector C2MN08C HLDF.
- Enable OBT ('ON') and select 2+0 mode.
- Select visible LED mode.
Yes - GO to A9.
No - Faulty fiber optic wiring harness between C23T pin 2 and C2MN08C pin 2; repair the problem and recheck the vehicle.
A9: HLDF fault check
Connect the optical link to the intermediate connector of the MOST C23T network. Is the reception indicator/LED constantly on and is there a blank screen on the HLDF display?
Yes - Check/repair power and ground lines to HLDF. If the power and ground lines are good, install a new HLDF. For more information, refer to: Video system display (415-01 Infotainment system, Removal and installation).
No - Check the integrity of the connections of the intermediate connector C23T and recheck the vehicle.
A10: Troubleshooting the fiber optic cable to the integrated audio unit
Disconnect the MOST network connector C2ME44B on the integrated audio unit. Can you see a bright red light on pin 1 of the C2ME44B MOST network connector, from the wiring harness side?
Yes - GO to A11.
No - Faulty fiber optic wiring harness between C23T pin 1 and C2ME44B pin 1; repair the problem and recheck the vehicle.
A11: Integrated audio unit fault check
- Connect the OBT to connector C2ME44B of the integrated MOST network audio unit.
- Enable OBT ('ON') and select 2+0 mode.
- Select visible LED mode.
Yes - Check/repair the power and ground lines to the integrated audio unit. If the power and ground lines are good, install a new integrated audio unit.
No - GO to A12.
A12: Troubleshooting the fiber optic cable coming from the integrated audio unit
- Disconnect the MOST network connector C2ME05B on the infotainment module.
- Enable OBT ('ON') and select 2+0 mode.
- Press the red 'TEST' button on the OBT and observe pin 1 of the C2ME05B connector, harness side
Yes - Install a new infotainment control module.
No - Faulty fiber optic wiring harness between C2ME05B pin 1 and C2ME44B pin 2; repair the problem and recheck the vehicle.
A13: checking for the presence of a navigation module
Check for a navigation module. Is there a navigation module on the car?
Yes - GO to A14.
No - GO to A16.
A14: Check for a fault in the fiber optic cable to the navigation module
Disconnect the MOST network connector C3MN08C on the navigation module. Can you see a bright red light on pin 1 of connector C3MN08C, from the harness side?
Yes - GO to A15.
No - Faulty fiber optic wiring harness between C3MN08C pin 1 and C23S pin 2; repair the problem and recheck the vehicle.
A15: check for a malfunction in the navigation module
- Connect the OBT to the MOST network connector C3MN08C of the navigation module.
- Enable OBT ('ON') and select 2+0 mode.
- Select visible LED mode.
Yes - Check/repair the power and ground lines to the navigation module. If the power and ground lines are good, install a new navigation module. For more information, see: DVD-Driven Navigation System (415-01 Infotainment system, Removal and installation).
No - Disconnect the OBT and dock the MOST network connector C3MN08C of the navigation module. GO to A16.
A16: Troubleshooting the fiber optic cable to the audio amplifier module
Disconnect the MOST network connector C4ME27C on the audio amplifier module. Can you see a bright red light on pin 1 of connector C4ME27C, from the harness side?
Yes - GO to A17.
No - Faulty fiber optic wiring harness between pin 2 of connector C3MN08C (or pin 2 of the C23S connector if the navigation module is not installed in the vehicle) and pin 1 of connector C4ME27C. Repair the problem and recheck the vehicle.
A17: Check for a malfunction in the audio amplifier module
- Connect the OBT to the connector of the C4ME27C MOST network audio amplifier module.
- Enable OBT ('ON') and select 2+0 mode.
- Select visible LED mode.
Yes - Check/repair the power and ground loops to the audio amplifier module. If the power and ground lines are good, install a new audio amplifier module. For more information refer to: Subwoofer Amplifier (415-01 Infotainment system, Removal and installation).
No - Disconnect the OBT and dock the connector of the C4ME27C MOST Network Audio Amplifier Module. GO to A18.
A18: check if bluetooth module is present
Check for a Bluetooth module. Does the car have a Bluetooth module?
Yes - GO to A19.
No - GO to A21.
A19: Check for a fault in the fiber optic cable to the bluetooth module
Disconnect the MOST network connector C4MM22B on the Bluetooth module. Can you see a bright red light on pin 1 of the C4MM22B connector, from the wiring harness side?
Yes - GO to A20.
No - Faulty fiber optic wiring harness between C4ME27C pin 2 and C4MM22B pin 1; repair the problem and recheck the vehicle.
A20: check for a malfunction of the bluetooth module
- Connect the OBT to the MOST network connector C4MM22B of the Bluetooth module.
- Enable OBT ('ON') and select 2+0 mode.
- Select visible LED mode.
Yes - Check/repair the power and ground lines to the Bluetooth module. If the power and ground lines are OK, install a new Bluetooth module. For more information refer to: Bluetooth module (415-01 Infotainment system, Removal and installation).
No - Disconnect the OBT and dock the MOST network connector C4MM22B of the Bluetooth module. GO to A21.
A21: Checking for the presence of a digital radio/satellite radio module
Check if you have a digital radio/satellite radio module. Is the vehicle equipped with a digital radio/satellite radio module?
Yes - GO to A22.
No - GO to A24.
A22: Check for a defect in the fiber optic cable to the digital broadcast/satellite radio module
Disconnect the MOST network connector C4ME43B on the digital radio/satellite radio module. Can you see a bright red light on pin 1 of connector C4ME43B, from the harness side?
Yes - GO to A23.
No - Faulty fiber optic wiring harness between pin 2 of connector C4MM22B (or pin 2 of the C4ME27C connector if the Bluetooth module is not installed in the vehicle) and pin 1 of connector C4ME43B. Repair the problem and recheck the vehicle.
A23: Check for a malfunction of the digital radio module / satellite radio
- Connect the OBT to the MOST network connector C4ME43B of the digital radio/satellite radio module.
- Enable OBT ('ON') and select 2+0 mode.
- Select visible LED mode.
Yes - Check/repair the power and ground lines to the digital radio/satellite radio module. If the power and ground lines are good, install a new digital radio/satellite radio module. For more information, refer to: Satellite radio receiver (415-01 Infotainment system, Removal and installation).
No - GO to A24.
A24: Check for a fault in the fiber optic cable to pin 1 of the intermediate connector C23S
- Disconnect the intermediate connector C23S.
- Enable OBT ('ON') and select 2+0 mode.
- Press the red 'TEST' button on the OBT and observe pin 1 of the C23S connector, from the harness side
Yes - No malfunction related to the MOST network is shown; check all connectors and recheck the car.
No - Faulty fiber optic harness between pin 2 of connector C4ME43B when a digital broadcast/satellite radio module is installed (or C4MM22B connector pin 2 if the digital radio/satellite radio module is not installed, or C4ME27C connector pin 2 if the Bluetooth module is not installed) and pin 1 of the C23S connector. Repair the problem and recheck the vehicle.
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