Precautions for Removing Battery Terminal: Notes

• When removing the 12v battery terminal, turn OFF the ignition switch and wait at least 5 minutes.
  NOTE: ECU may be active for several minutes after the ignition switch is turned OFF. If the battery terminal is removed before ECU stops, then a DTC detection error or ECU data corruption may occur.
• Disconnect 12v battery terminal according to the following steps.

Fig 1: Disconnecting Battery Negative Terminal

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