DTC U1B01[66] Unauthorized Signal Reception with ECM (Wireless Access Module (Mid-version/Lo-version [Except Passive Entry and Start System]))

1. DTC U1B01[66] description

When the transponder authentication is completed, the wireless access module starts authentication with the ECM. The ECM sends a specific request signal to the wireless access module, and the wireless access module sends back a response signal to the ECM. Communication between the wireless access module and the ECM is done via the CAN communication circuit. If the wireless access module M cannot receive a request signal from the ECM, the DTC is set.

2. Condition for setting DTC U1B01[66]

Condition for running the DTC

  • Models with immobilizer function
  • The ignition switch is ON.

Condition for setting the DTC

  • The wireless access module receives authentication requests from the ECM over 20 times in 1 ignition cycle.

3. Action taken when DTC U1B01[66] sets

When the ignition switch is ON:

  • The key monitor warning light illuminates.
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