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Home >> Toyota >> 2019 >> RAV4 LE, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Smart Key System (For Start, Except HV) - Diagnostic Codes (2 Of 2) & Symptom Tests (1 Of 2) >> SMART KEY SYSTEM (for Start Function, Gasoline Model) >> DTC U0100: Lost Communication with ECM / PCM; 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 U1103: Lost Communication with Stop and Start Control Module; DTC U1117: Lost Communication with Accessory Gateway [11/2018 - ] >> Description
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DTC U0100: Lost Communication with ECM / PCM; 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 U1103: Lost Communication with Stop and Start Control Module; DTC U1117: Lost Communication with Accessory Gateway [11/2018 - ]: Description

These DTCs are stored when there is a CAN communication malfunction between the certification ECU (smart key ECU assembly), ECM, main body ECU (multiplex network body ECU), shift lock control unit assembly, combination meter assembly, multiplex network door ECU*1 or engine stop and start ECU*2.

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

  1. *1: w/ Power Back Door System
  2. *2: w/ Stop and Start System
DTC No. Detection Item DTC Detection Condition Trouble Area Note
U0100 Lost Communication with ECM / PCM CAN communication malfunction between certification ECU (smart key ECU assembly) and ECM (1-trip detection logic*) ECM DTC Output Confirmation Operation: 
  1. Turn the engine switch on (IG) and wait at least 10 seconds.
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 engine switch on (IG) and wait at least 10 seconds.
U0230 Lost Communication with Rear Gate Module CAN communication malfunction between certification ECU (smart key ECU assembly) and multiplex network door ECU (1 trip detection logic*) Multiplex network door ECU DTC Output Confirmation Operation: 
  1. Turn the engine switch on (IG) and wait at least 3 seconds.
U1103 Lost Communication with Stop and Start Control Module CAN communication malfunction between the certification ECU (smart key ECU assembly) and engine stop and start ECU (1-trip detection logic*). Engine stop and start ECU DTC Output Confirmation Operation: 
  1. Turn the engine 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 engine 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
U0100 There is no effect on vehicle behavior. If the following conditions are met, it is determined that the malfunction is not in the direct line (NE) but in CAN communication.
  • When the engine switch is pressed, the system controls the engine based on the engine speed signal via direct line, causing the engine to stop cranking.
  • When the engine switch is pressed and held, the system controls the engine based on the engine speed signal via direct line, causing the engine to stop cranking.

If the following conditions are met, it is determined that there is a malfunction in both CAN communication and the direct line (NE).
  • When the engine switch is pressed, the engine stops cranking after 6 seconds.
  • When the engine switch is pressed and held, the engine remains cranking for up to 30 seconds.
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 back door does not operate. -
U1103
  • The engine stall misjudgment is done by the idling stop by stop and start system.
  • Immobiliser set is done by the door operation in the idling stop by stop and start system
 -
U1117 The engine cannot be started using the wireless remote control function. -
RELATED DATA LIST AND ACTIVE TEST ITEMS

DTC No. Data List and Active Test
U0100
U0140
U0142
U0155
U0230
U1103
U1117		 -
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