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Home >> Lexus >> 2021 >> NX 300h Base >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Smart Access System With Push-Button Start (For Start Function) - Diagnostic Codes & Symptom Tests >> SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) >> DTC U0140: Lost Communication with Main Body ECU; DTC U0142: Lost Communication with Main Body ECU; DTC U0155: Lost Communication with Combination Meter; DTC U0293: Lost Communication with Hybrid Vehicle Control System; DTC U1117: Lost Communication with Accessory Gateway [10/2014 - ] >> Description
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DTC U0140: Lost Communication with Main Body ECU; DTC U0142: Lost Communication with Main Body ECU; DTC U0155: Lost Communication with Combination Meter; DTC U0293: Lost Communication with Hybrid Vehicle Control System; DTC U1117: Lost Communication with Accessory Gateway [10/2014 - ]: Description

These DTCs are stored when there is a CAN communication error between the hybrid vehicle control ECU, certification ECU (smart key ECU assembly), ECM, main body ECU (multiplex network body ECU) or combination meter assembly, and data from the option connector (bus buffer ECU) cannot be received.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
U0140 Lost Communication with Main Body ECU CAN communication error between certification ECU (smart key ECU assembly) and main body ECU (multiplex network body ECU) (1-trip detection logic*) Main body ECU (multiplex network body ECU) DTC Output Confirmation Operation: 
  1. Always
U0142 Lost Communication with Main Body ECU CAN communication error between certification ECU (smart key ECU assembly) and main body ECU (multiplex network body ECU) (1-trip detection logic*) Main body ECU (multiplex network body ECU) DTC Output Confirmation Operation: 
  1. Always
U0155 Lost Communication with Combination Meter CAN communication error between certification ECU (smart key ECU assembly) and combination meter assembly (1-trip detection logic*) Combination meter assembly DTC Output Confirmation Operation: 
  1. Turn the power switch on (IG) and wait 10 seconds or more.
U0293 Lost Communication with Hybrid Vehicle Control System CAN communication error between certification ECU (smart key ECU assembly) and hybrid vehicle control ECU (1-trip detection logic*) Hybrid vehicle control ECU DTC Output Confirmation Operation: 
  1. Turn the power switch on (IG) and wait 10 seconds or more.
U1117 Lost Communication with Accessory Gateway Data from the option connector (bus buffer ECU) cannot be received.
  • Connector and branch wire of sub bus 2 of option connector (bus buffer ECU)
  • Internal malfunction of option connector (bus buffer ECU)
 DTC Output Confirmation Operation: 
  1. Turn the power switch on (IG) and wait 10 seconds or more.
  1. *: Only detected while a malfunction is present.
VEHICLE CONDITION AND FAIL-SAFE FUNCTION WHEN MALFUNCTION DETECTED

DTC No. Vehicle Condition when Malfunction Detected Fail-safe Function when Malfunction Detected
U0140 The warning (meter buzzer) does not sound and the meter does not indicate a warning. -
U0142
  • Doors cannot be locked or unlocked.
  • The warning (meter buzzer) does not sound and the meter does not indicate a warning.
 -
U0155
  • The warning (meter buzzer) does not sound and the meter does not indicate a warning.
  • There is no effect on vehicle behavior.
 -
U0293 The warning (meter buzzer) does not sound and the meter does not indicate a warning. -
U1117 The hybrid control system cannot be started using the wireless remote control function. -
RELATED DATA LIST AND ACTIVE TEST ITEMS

DTC No. Data List and Active Test
U0140
U0142
U0155
U0293
U1117		 -
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