B210E
DTC B210D: Battery Voltage LowDTC B210E: Battery Voltage High
Occupant Classification-ECU Power Supply Circuit:
CAUTION: If DTC B210D, B210E is set in the occupant classification-ECU, always diagnose the CAN main bus lines.
TROUBLE JUDGEMENT
The occupant classification-ECU sets DTC B210D if the power supply fuse voltage decreases to the specified value or less, and sets DTC B210E if the power supply fuse voltage increases to the specified value or more. However, when the status returns to normal, the occupant classification-ECU automatically erases DTCs B210D and B210E.
TECHNICAL DESCRIPTION (COMMENT)
The power supply fuse or the occupant classification-ECU may have a problem.
TROUBLESHOOTING HINTS
- The power supply fuse may be defective.
- The occupant classification-ECU may be defective.
- The battery may be defective.
- The alternator may be defective.
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
DIAGNOSIS
Required Special Tools:
- 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 (Vehicles with CAN communication system)
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
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". Scan Tool Connecting
2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?
YES : Go to Step 2.
NO : Repair the CAN bus line (Refer to Controller area network Diagnosis).
STEP 2. Recheck for diagnostic trouble code.
Check again if the DTC is set.
1. Erase the DTC.
2. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
3. Check if DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Go to Step 3
NO : There is an intermittent malfunction such as poor engaged connector(s) or open circuit (Refer to general (Body and Chassis) How to use Troubleshooting/inspection Service Points).
STEP 3. Check the occupant classification-ECU connector D-35-2 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is the occupant classification-ECU connector D-35-2 in good condition?
YES : Go to Step 4.
NO : Repair or replace the component(s) (Refer to general (electrical), Harness Connector Inspection).
STEP 4. Check the battery power supply circuit to the occupant classification-ECU. Measure the voltage at occupant classification-ECU connector D-35-2.
1. Disconnect occupant classification-ECU connector D-35-2 and measure the voltage available at the wiring harness side of the connector.
2. Measure the voltage between terminal 21 and ground.
- The voltage should measure approximately 12 volts (battery positive voltage).
Q: Is the measured voltage approximately 12 volts (battery positive voltage)?
YES : Go to Step 6.
NO : Go to Step 5.
STEP 5. Check the wiring harness between the occupant classification-ECU connector D-35-2 (terminal 21) and the fusible link (17).
Q: Is the wiring harness between occupant classification-ECU connector D-35-2 (terminal 21) and the fusible link (17) in good condition?
YES : No action is necessary and testing is complete.
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. Using scan tool MB991958, check data list.
Check the power supply fuse voltage.
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 the "ON" position.
3. Check the occupant classification-ECU data list.
- Turn the ignition switch to the "ACC" position.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Do the scan tool MB991958 display the item "battery voltage" is normal condition?
YES : Go to Step 7.
NO : Replace the front seat cushion frame (Refer to Interior Front seat assembly).
STEP 7. Recheck for diagnostic trouble code.
Check again if the DTC is set to the occupant classification-ECU.
1. Erase the DTC.
2. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
3. Check if DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Replace the front seat cushion frame (Refer to Interior Front Seat Assembly).
NO : There is an intermittent malfunction such as poor engaged connector(s) or open circuit (Refer to general (Body and Chassis) How to use Troubleshooting/inspection Service Points).