Code No.C2100: Power supply low voltage


caution
  • When the ETACS-ECU of vehicles without KOS is replaced, the encrypted code of the ignition key needs to be registered to the ETACS-ECU. (If the encrypted code is not registered, the engine cannot be started. Register the encrypted code as described in GROUP 54A, Immobilizer System - How to Register Key ID .)

OPERATION



DIAGNOSIS CODE SET CONDITIONS




  • Voltage between the battery and ETACS-ECU: Less than 9 V

PROBABLE CAUSES



  • Battery failure
  • Malfunction of charging system
  • Malfunction of ETACS-ECU (power supply circuit system)
  • Damaged harness wires and connectors
  • Malfunction of electronic control coupling solenoid
  • Malfunction of 4WD-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III other system diagnosis code.
Check the ETACS diagnosis code (Refer to GROUP 54A - Troubleshooting ).

Q. Is the diagnosis code set?
Perform the relevant troubleshooting.
Go to Step 2.

STEP 2. Check the battery.
Refer to GROUP 54A - Battery Test .

Q. Is the check result normal?
Go to Step 4.
Charge or replace the battery. Then go to Step 3.

STEP 3. Check the charging system.
Refer to GROUP 16 - Charging System .

Q. Is the check result normal?
Go to Step 4.
Repair or replace the charging system component(s).

STEP 4. Voltage measurement at 4WD-ECU connector
Disconnect the connector, and measure the voltage between terminal BAtt and body earth at the wiring harness side.
OK: System voltage

Q. Is the check result normal?
Go to Step 6.
Repair the defective connector or the wiring harness. Then go to Step 5.

STEP 5. M.U.T.-III data list.
Check the following data list (Refer to ).

  • Item No.31: Battery voltage (CAN input)

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
Replace the ETACS-ECU. Then go to Step 10.

STEP 6. Check the wiring harness between 4WD-ECU connector terminal GND1 and body earth.
Check the earth line for open circuit.

Q. Is the check result normal?
Go to Step 7.
Repair the defective connector or the wiring harness. Then go to Step 10.

STEP 7. Check the wiring harness between electronic control coupling solenoid connector and 4WD-ECU connector terminal SOL+, SOL-.
Check the power supply, earth line for short circuit.

Q. Is the check result normal?
Go to Step 8.
Repair the defective connector or the wiring harness. Then go to Step 10.

STEP 8. Check of the electronic control coupling solenoid
Refer to .

Q. Is the check result normal?
Go to Step 9.
Replace the electronic control coupling (Refer to ). Then go to Step 10.

STEP 9. M.U.T.-III data list.
Check the following data list (Refer to ).

  • Item No.31: Battery voltage (CAN input)

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
Replace the 4WD-ECU (Refer to ). Then go to Step 10.

STEP 10. Check whether the diagnosis code is reset.

Q. Is diagnosis code No.C2100 set?
Return to Step 1.
This diagnosis is complete.