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


These diagnosis codes are set when the IG voltage decreases to the specified value or less (code No. B2353) or increases to the specified value or more (code No. B2354). However, when the status returns to normal, the code Nos. B2353 and B2354 are automatically erased.

COMMENTS ON TROUBLE SYMPTOM


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

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


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


Check the IG voltage.

Item No.
Item name
Normal condition
Item 254
IG voltage
System voltage
OK: Normal condition is displayed.

Q. Is the check result normal?

Go to Step 6.

Go to Step 2.

STEP 2. Battery check


Refer to GROUP 54A - Battery Test .

Q. Is the battery in good condition?

Go to Step 3.

Charge or replace the battery.

STEP 3. Charging system check


Refer to GROUP 16 - Charging System .

Q. Is the charging system in good condition?

Go to Step 4.

Repair or replace the charging system component(s).

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?

Go to Step 6.

Go to Step 5.

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?

Refer to Inspection Procedure 2 "Malfunction of the ignition switch power supply system."

Repair the connector(s) or wiring harness.

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 ).