Inspection Procedure 4: The radio broadcasting cannot be received. <Digital radio (vehicles with DAB tuner)>
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Whenever the multivision display is replaced, ensure that the power supply circuit and the earthing circuit are normal. (Check that the voltage is 10 V or more.)
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COMMENTS ON TROUBLE SYMPTOM
In case of digital radio broadcasting cannot be received, digital audio broadcast (DAB) tuner, antenna rod, antenna base <Vehicles with roof antenna>, glass antenna (radio amplifier) <Vehicles with glass antenna>, antenna feeder or multivision display may have a problem.
PROBABLE CAUSES
- Malfunction of DAB tuner
- Malfunctions of antenna rod <Vehicles with roof antenna>
- Malfunctions of antenna base <Vehicles with roof antenna>
- Malfunctions of glass antenna (radio amplifier) <Vehicles with glass antenna>
- Malfunction of antenna feeder
- Malfunction of multivision display
- Damaged harness wires and connectors
DIAGNOSIS PROCEDURE
STEP 1. Confirmation in MMCS service mode.
Perform "Communications & Connection Check" in the MMCS service mode to check that the communication and wire connection with the Digital Radio are OK (Refer to 
).
Q.
Is the check result normal?
Go to Step 7.
Go to Step 2.
STEP 2. Voltage measurement at DAB tuner connector (+B terminal).
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(1)Disconnect the connector, and measure at the wiring harness side.
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(2)Check the voltage between the DAB tuner connector (+B terminal) and body earth.
OK: System voltage
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Q.
Is the check result normal?
Go to Step 4.
Go to Step 3.
STEP 3. Check of short to earth, and open circuit in +B line between DAB tuner connector and fusible link.
Q.
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction).
Repair the connector(s) or wiring harness.
STEP 4. Resistance measurement at DAB tuner connector (GND terminal).
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(1)Disconnect the connector, and measure at the wiring harness side.
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(2)Check the continuity between the DAB tuner connector (GND terminal) and body earth.
OK: Continuity exists (2 Ω or less)
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Q.
Is the check result normal?
Go to Step 6.
Go to Step 5.
STEP 5. Check of open circuit in GND line between DAB tuner connector and body earth.
Q.
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction).
Repair the connector(s) or wiring harness.
STEP 6. Check of short or open circuit in TIL+, TIL-, TIR+, TIR-, TSHG, ACC, IEH, IEL line between DAB tuner connector and multivision display connector.
Q.
Is the check result normal?
Go to Step 7.
Repair the connector(s) or wiring harness.
STEP 7. Check the state of the antenna rod and antenna base.
Q.
Is the antenna assembled?
Go to Step 8.
Assemble antenna rod and antenna base.
STEP 8. Check if there is any damage to the antenna rod, antenna base and antenna feeder.
Q.
Is the check result normal?
Go to Step 9.
Replace the antenna rod, antenna base and antenna feeder.
STEP 9. Check the connection of the antenna feeder’s plug and DAB tuner.
Q.
Is the antenna feeder’s plug thoroughly connected to the DAB tuner?
Go to Step 10.
Thoroughly connect the antenna feeder’s plug and the DAB tuner.
STEP 10. Substitute a known good multivision display, and check the trouble symptom.
Q.
Is the check result normal?
Replace the multivision display.
Replace the DAB tuner.