CODE NO. B210D Battery abnormal low voltage












caution If the diagnosis code B210D is set to SRS-ECU, be sure to diagnose the CAN bus line.

OPERATION
The battery power supply is supplied from the ignition switch (IG1) to SRS-ECU.
SRS-ECU has two independent battery power supplies circuit (fuse Nos. 12 and 18) having fuses.

TROUBLE JUDGMENT
The code is set when the voltage between the IG1 terminal (SRS-ECU terminal No. 61 or No. 62) and the earth drops below the specified value for 5 seconds continuously.

PROBABLE CAUSES

  • Battery voltage drop
  • Open circuit to power supply circuit
  • Damaged wiring harness and connectors
  • Malfunction of SRS-ECU

DIAGNOSIS PROCEDURE

STEP 1. Battery check.
Refer to GROUP 54A - Battery Test .

Q. Is the check result normal?
Go to Step 2.
Charge or replace the battery.

STEP 2. Measure the voltage at the ETACS-ECU connector.
(1)Disconnect the C-309 ETACS-ECU connector.
(2)Measure the voltage between the C-309 harness side connector terminal No. 1 and the body earth.
OK: Battery voltage

Q. Is the check result normal?
Go to Step 4.
Go to Step 3.

STEP 3. Wiring harness check between the fusible link (33) and the C-309 ETACS-ECU connector terminal No. 1.

  • Open circuit check for ETACS-ECU power supply wire

Q. Is the check result normal?
Go to Step 8.
Repair the wiring harness.

STEP 4. M.U.T.-III other system diagnosis code.
Check if the ETACS diagnosis code is set.

Q. Is the diagnosis code set?
Diagnose the ETACS (Refer to Group 54A - ETACS - Troubleshooting ).
Go to Step 5.

STEP 5. M.U.T.-III CAN bus diagnostics.
Use M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 6.
Repair the CAN bus lines (Refer to Group 54C - Troubleshooting ).

STEP 6. Check whether the diagnosis code is reset.
(1)Connect the negative battery terminal.
(2)After erasing the diagnosis code memory, check the diagnosis code again.
(3)Disconnect the negative battery terminal.

Q. Is the diagnosis code No. B210D set?
Go to Step 7.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).

STEP 7. Resistance measurement at the C-31 SRS-ECU connector.
(1)Check that the negative battery terminal is disconnected. If the negative battery terminal is connected, disconnect it.
(2)Disconnect the C-313 ETACS-ECU connector.

(3)While pushing the part "A" indicated in the figure of the harness side connector, turn the lock lever to the direction of the arrow to release the lock lever, and disconnect the C-31 SRS-ECU connector.
(4)Measure the resistance values as shown below.

  • Continuity between C-313 ETACS-ECU connector terminal No. 2 and C-31 SRS-ECU connector terminal No. 62
  • Continuity between C-313 ETACS-ECU connector terminal No. 4 and C-31 SRS-ECU connector terminal No. 61
OK: Continuity (less than 2 Ω)

Q. Is the check result normal?

Go to Step 8.

Repair the wiring harness between the C-313 ETACS-ECU connector terminal No. 2/4 and the C-31 SRS-ECU connector terminal No. 62/61.

STEP 8. Check whether the diagnosis code is reset.

Q. Is the diagnosis code No. B210D set?
Replace SRS-ECU (Refer to ).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).