B2450
Code NO.B2450: Switch Panel CommunicationCAUTION:
- If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, always diagnose the CAN bus lines.
- Before replacing the radio and CD player or CD changer, be sure to check that the power supply circuit, ground circuit, and communication circuit are normal.
Center Panel Unit Power Supply Circuit (Part 1):
Center Panel Unit Power Supply Circuit (Part 2):
TROUBLE JUDGEMENT
If the radio and CD player or CD changer cannot establish the communication with center panel assembly for 1 minute or more, the diagnostic trouble code is set.
COMMENTS ON TROUBLE SYMPTOM
The radio and CD player or CD changer, center panel assembly, or CAN bus line may have a problem.
PROBABLE CAUSES
- Malfunctions of radio and CD player or CD changer
- Malfunction of center panel assembly
- Malfunction of CAN bus line wiring harness and connector
DIAGNOSIS
Required Special Tools:
- MB991223: Harness Set
- B992006: Extra Fine Probe
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
Use scan tool MB991958 to diagnose the CAN bus lines.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958. Refer to "How to connect the Scan Tool (M.U.T.-III)." Scan Tool Connecting
2. Turn the ignition switch to "ON" position.
3. Diagnose the CAN bus line.
Q: Is the check result normal?
YES : Go to Step 2.
NO : Repair the CAN bus line (Refer to Controller area network Diagnosis).
STEP 2. Check center panel unit connector C-104 and radio and CD player or CD changer connector C-14 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are center panel unit connector C-104 and radio and CD player or CD changer connector C-14 in good condition?
YES : Go to Step 3.
NO : Repair or replace the damaged component(s) (Refer to general (electrical) Harness Connector Inspection).
STEP 3. Check the wiring harness between center panel unit connector C-104 (terminal 1, 2) and radio and CD player or CD changer connector C-14 (terminal 8, 18).
Q: Is the wiring harness between center panel unit connector C-104 (terminal 1, 2) and radio and CD player or CD changer connector C-14 (terminal 8, 18) in good condition?
YES : Go to Step 4.
NO : The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.
STEP 4. Check the ground circuit to the center panel unit. Measure the resistance at center panel unit connector C-104.
1. Disconnect the connector, and measure at the wiring harness side.
2. Measure resistance between terminal 9 and ground.
OK: The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 6.
NO : Go to Step 5.
STEP 5. Check the wiring harness between center panel unit connector C-104 (terminal 9) and ground.
- Check the ground wires for open circuit.
Q: Is the wiring harness between center panel unit connector C-104 (terminal 9) and ground in good condition?
YES : Go to Step 8.
NO : The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.
STEP 6. Check the power supply circuit to the center panel unit. Measure the voltage at center panel unit connector C-104.
1. Disconnect the connector, and measure at the harness side connector.
2. Measure voltage between terminal 7 and ground.
OK: Battery voltage
Q: Is the measured voltage battery voltage?
YES : Go to Step 8.
NO : Go to Step 7.
STEP 7. Check the wiring harness between center panel unit connector C-104 (terminal 7) and fusible link 34.
- Check the power supply line for open circuit and short circuit.
NOTE: Also ETACS-ECU connector C-307, C-317 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If joint connector ETACS-ECU connector C-307, C-317 are damaged, repair or replace the connector as described in general (electrical), Harness Connector Inspection.
Q: Is the wiring harness between center panel unit connector C-124 (terminal 7) and fusible link 34 in good condition?
YES : Go to Step 8.
NO : The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.
STEP 8. Recheck for diagnostic trouble code.
Check again if the DTC is set to the radio and CD player or CD changer.
1. Erase the DTC.
2. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
3. Check if the DTC is set.
Q: Is the DTC set?
YES : Go to Step 9.
NO : The trouble can be an intermittent malfunction (Refer to general (Body and Chassis) How to use Troubleshooting/inspection Service Points, How to Cope with Intermittent Malfunction).
STEP 9. Recheck for diagnostic trouble code.
Temporarily replace the center panel unit, and recheck whether the DTC is set to the radio and CD player or CD changer.
1. Erase the DTC.
2. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
3. Check if the DTC is set.
Q: Is the DTC set?
YES : Replace the radio and CD player or CD changer.
NO : Replace the center panel unit.