DTC U1821[86] Invalid Data Received from ABS (Wireless Access Module (Mid-version/Lo-version [Except Passive Entry and Start System]))

1. DTC U1821[86] description

The wireless access module and EHCU communicate the control information and diagnosis information via the CAN communication circuit. The wireless access module monitors the CAN operational status by expecting a constant message flow from the EHCU. If the wireless access module cannot receive the wheel speed data from the ECM, the DTC is set.

2. Condition for setting DTC U1821[86]

Condition for running the DTC

  • The ignition switch is ON.

Condition for setting the DTC

  • The wireless access module detects that the wheel speed data from the EHCU has not been received for 5 seconds or the data indicating a malfunction has been received 25 consecutive times.
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