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. B1E18 will be set when the left taillight control circuit in the ETACS-ECU fails.
TECHNICAL DESCRIPTION (COMMENT)
DTC No. B1E18 will be set when the ETACS-ECU detects a short to ground in its left taillight control circuit.
TROUBLESHOOTING HINTS
The left taillight control circuit fails
The ETACS-ECU may be defective
DIAGNOSIS
Using scan tool (M.U.T.-III), read the ETACS-ECU diagnostic trouble code.
Check if the DTC No. B16A8 is set to the ETACS-ECU.
Is the DTC set?
Carry out the troubleshooting for DTC No. B16A8. On completion, replace the ETACS-ECU when it has not been replaced as the troubleshooting process for DTC No. B16A8. This is because DTC No. B1E18 cannot be erased.
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Carry out the troubleshooting for DTC No. B16A8. On completion, replace the ETACS-ECU when it has not been replaced as the troubleshooting process for DTC No. B16A8. This is because DTC No. B1E18 cannot be erased.
Replace the ETACS-ECU.