Code No.B210A +B power supply (low input)
Code No.B210B +B power supply (high input)



caution Before replacing the ECU, ensure that the input and output signal circuits are normal.








TROUBLE JUDGMENT


The ETACS-ECU sets the code No. B210A if the power supply fuse voltage decreases to the specified value or less, and sets the code No. B210B if the power supply fuse voltage increases to the specified value or more. However, when the status returns to normal, the ETACS-ECU automatically erases the code Nos. B210A and B210B.

COMMENTS ON TROUBLE SYMPTOM


The power supply fuse or the ETACS-ECU may have a problem.

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


STEP 1. Power supply fuse check


Q. Is the fuse in good condition?

Go to Step 2.
Replace the power supply fuse, and then go to Step 6.

STEP 2. Connector check: C-307 ETACS-ECU connector


Q. Is the check result normal?

Go to Step 3.
Repair the defective connector.

STEP 3. Voltage measurement at the C-307 ETACS-ECU connector.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the voltage between the C-307 ETACS-ECU connector terminal No. 2 and the body earth.
OK: Battery voltage

Q. Is the check result normal?

Go to Step 5.
Go to Step 4.

STEP 4. Wiring harness check between the C-307 ETACS-ECU connector terminal No. 2 and the fusible link (34)


Check the power supply line for open circuit.

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 wiring harness.

STEP 5. M.U.T.-III data list


Check the power supply fuse voltage.

  • Ignition switch: OFF
Item No.
Item name
Normal condition
Item 253
Voltage sensing of IOD Line
Battery voltage
OK: Normal condition is displayed.

Q. Is the check result normal?

Go to Step 6.
Replace the ETACS-ECU.

STEP 6. Check whether the diagnosis code is reset.


Check again if the diagnosis code is set to the ETACS-ECU.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3)Check if diagnosis code is set.

Q. Is the diagnosis code set?

Replace the ETACS-ECU.
The trouble can be an intermittent malfunction (GROUP 00 - How to use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).