Before replacing the ECU, ensure that the power supply circuit, the ground 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 JUDGMENT
DTC No. B1E21 will be set when the ETACS-ECU detects an internal fault at LO side of the dome light.
TECHNICAL DESCRIPTION (COMMENT)
DTC No. B1E21 will be set when the ETACS-ECU detects a internal fault at LO side of the dome light.
TROUBLESHOOTING HINTS
The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
The ETACS-ECU may be defective
DIAGNOSIS
Using scan tool (M.U.T.-III), read the ETACS-ECU diagnostic trouble code.
Check if DTC No. B1E1E is set in the ETACS-ECU.
Is the DTC set?
Carry out the troubleshooting for DTC No. B1E1E. On completion, replace the ETACS-ECU when it has not been replaced as the troubleshooting process for DTC No. B1E1E. This is because DTC No. B1E21 cannot be erased.
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Carry out the troubleshooting for DTC No. B1E1E. On completion, replace the ETACS-ECU when it has not been replaced as the troubleshooting process for DTC No. B1E1E. This is because DTC No. B1E21 cannot be erased.
Replace the ETACS-ECU.