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Home >> Lexus >> 2021 >> LS 500h RWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Smart Access System (For Start) - Diagnostic Codes & Symptom Tests (1 Of 2) >> SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) >> DTC U0103: Lost Communication with Gear Shift Module "A"; DTC U0129: Lost Communication with Brake System Control Module; DTC U0140: Lost Communication with Body Control Module; DTC U0142: Lost Communication with Main Body ECU; DTC U0155: Lost Communication with Combination Meter; DTC U0230: Lost Communication with Rear Gate Module; DTC U1117: Lost Communication with Accessory Gateway [10/2017 - 10/2020] >> Description
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DTC U0103: Lost Communication with Gear Shift Module "A"; DTC U0129: Lost Communication with Brake System Control Module; DTC U0140: Lost Communication with Body Control Module; DTC U0142: Lost Communication with Main Body ECU; DTC U0155: Lost Communication with Combination Meter; DTC U0230: Lost Communication with Rear Gate Module; DTC U1117: Lost Communication with Accessory Gateway [10/2017 - 10/2020]: Description

These DTCs are stored when there is a CAN communication malfunction between the certification ECU (smart key ECU assembly), hybrid vehicle control ECU assembly, main body ECU (multiplex network body ECU), shift control ECU, combination meter assembly or luggage closer motor assembly.

Data from the option connector (bus buffer ECU) cannot be received.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
U0103 Lost Communication with Gear Shift Module "A" CAN communication error between the certification ECU (smart key ECU assembly) and hybrid vehicle control ECU assembly (1-trip detection logic*) Shift control ECU DTC Output Confirmation Operation: 
  1. Turn the power switch on (IG) and wait at least 5 seconds.
U0129 Lost Communication with Brake System Control Module CAN communication error between the certification ECU (smart key ECU assembly) and skid control ECU (brake booster with master cylinder assembly) (1-trip detection logic*) Skid Control ECU (Brake Booster with Master Cylinder Assembly) DTC Output Confirmation Operation: 
  1. Always
U0140 Lost Communication with Body Control Module CAN communication malfunction 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. Any time
U0142 Lost Communication with Main Body ECU CAN communication malfunction 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. Any time
U0155 Lost Communication with Combination Meter CAN communication malfunction 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 at least 10 seconds.
U0230 Lost Communication with Rear Gate Module CAN communication malfunction between smart key ECU assembly (certification ECU) and luggage closer motor assembly (1 trip detection logic*) Luggage Closer Motor Assembly DTC Output Confirmation Operation: 
  1. Turn the power switch on (IG) and wait at least 3 seconds.
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 at least 10 seconds.
  1. *: Only detected while a malfunction is present.
VEHICLE CONDITION AND FAIL-SAFE FUNCTION WHEN MALFUNCTION DETECTED

DTC Code Vehicle Condition when Malfunction Detected Fail-safe Function when Malfunction Detected
U0103 The shift state does not change from park (P) to shift state other than park (P). -
U0129 Hybrid control system does not start. -
U0140 The warning (meter buzzer) does not sound and no warning messages displayed on the multi-information display. -
U0142
  • Doors cannot be locked or unlocked.
  • The warning (wireless buzzer) does not sound.
 -
U0155
  • The warning (meter buzzer) does not sound and the meter does not indicate a warning.
  • There is no effect on vehicle behavior.
 -
U0230 Power trunk lid does not operate. -
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
U0103
U0129
U0140
U0142
U0155
U0230
U1117		 -
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