Code No.B2353 Ignition power supply (low)
Code No.B2354 Ignition power supply (high)


caution
  • Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.
  • 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 Immobilizer System - How to Register Key ID .)

TROUBLE JUDGEMENT



COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of power supply circuit
  • Malfunction of the battery
  • Malfunction of the alternator
  • Malfunction of harness
  • Malfunction of the ignition switch
  • Malfunction of the ETACS-ECU
  • Malfunction of the OSS-ECU <Vehicles with one touch start system>

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III data list




  • Turn the ignition switch to the ON position.
Item No.
 Item name
 Normal condition
Item 254
 IG voltage
 System voltage
OK: Normal condition is displayed.

Q. Is the check result normal?





STEP 2. Battery check



Q. Is the battery in good condition?





STEP 3. Charging system check



Q. Is the charging system in good condition?





STEP 4. Voltage measurement at ETACS-ECU connector (IG1 terminal)


(1)Measure by backprobing without disconnecting the connector.
(2)Turn the ignition switch to the "ON" position.
(3)Check the voltage between the ETACS-ECU connector (IG1 terminal) and body earth.
OK: System voltage

Q. Is the check result normal?





STEP 5. Check of short to power supply, short to earth, and open circuit in ETACS +B line between ignition switch (IG1) <vehicles without one touch start system>or OSS-ECU (IG1) connector <vehicles with one touch start system> and ETACS-ECU connector


Q. Is the check result normal?





STEP 6. Check whether the diagnosis code is reset.



(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?