DTC U1840[86] BCM Communication Interruption/Data Malfunction (eCall unit)

1. DTC U1840[86] description

The eCall unit communicates the control information with the BCM via the CAN communication circuit. If the eCall unit cannot receive the control information sent from the BCM, the DTC is set.

2. Condition for setting DTC U1840[86]

Condition for running the DTC

  • The ignition switch is ON.
  • The ignition voltage is 9 V or more.

Condition for setting the DTC

  • The eCall unit detects that the control information sent from the BCM cannot be received for 5 seconds or more.

3. Action taken when DTC U1840[86] sets

  • The indicator light (red) illuminates.
  • An alarm sounds from the speaker.
  • Current and past failures are set.
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