Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Diagnostic Trouble Code Chart

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Power Source & Network / Networking / Can Communication System / Diagnostic Trouble Code Chart

DIAGNOSTIC TROUBLE CODE CHART

Diagnostic Trouble Code Chart

DTC No.

Detection Item

Trouble Area

Note

Link

B1003

ECU Malfunction

Network gateway ECU

-

U0199

Lost Communication with "Door Control Module A"
  • Outer mirror control ECU assembly (for front passenger side) branch line or connector
  • Power source circuit of outer mirror control ECU assembly (for front passenger side)
  • Outer mirror control ECU assembly (for front passenger side) ground circuit
  • Outer mirror control ECU assembly (for front passenger side)

HINT:

The main body ECU (multiplex network body ECU) stores DTCs when it detects a communication stop or network communication error for ECUs connected to sub bus 1.

U0200

Lost Communication with "Door Control Module B"
  • Outer mirror control ECU assembly (for driver side) branch line or connector
  • Power source circuit of outer mirror control ECU assembly (for driver side)
  • Outer mirror control ECU assembly (for driver side) ground circuit
  • Outer mirror control ECU assembly (for driver side)

HINT:

The main body ECU (multiplex network body ECU) stores DTCs when it detects a communication stop or network communication error for ECUs connected to sub bus 1.

U0208

Lost Communication with "Seat Control Module A"
  • Position control ECU and switch assembly LH branch line or connector
  • Power source circuit of position control ECU and switch assembly LH
  • Position control ECU and switch assembly LH ground circuit
  • Position control ECU and switch assembly LH

HINT:

The main body ECU (multiplex network body ECU) stores DTCs when it detects a communication stop or network communication error for ECUs connected to sub bus 1.

U0230

Lost Communication with Rear Gate Module
  • Multiplex network door ECU branch line or connector
  • Power source circuit of multiplex network door ECU
  • Multiplex network door ECU ground circuit
  • Multiplex network door ECU

HINT:

The main body ECU (multiplex network body ECU) stores DTCs when it detects a communication stop or network communication error for ECUs connected to sub bus 1.

U1002

Lost Communication with Gateway Module (Main Body ECU)
  • Open or short in sub bus 1 main lines or connector
  • Short in sub bus 1 branch lines or connector
  • Main body ECU (multiplex network body ECU)
  • Outer mirror control ECU assembly (for driver side)
  • Outer mirror control ECU assembly (for front passenger side)
  • Position control ECU and switch assembly LH (w/ Seat Position Memory System)
  • Multiplex tilt and telescopic ECU
  • Multiplex network door ECU
  • Open or short in No. 8 CAN junction connector
  • Open or short in No. 11 CAN junction connector
  • Open or short in No. 1 CAN junction terminal

HINT:

The main body ECU (multiplex network body ECU) stores DTCs when it detects a communication stop or network communication error for ECUs connected to sub bus 1.

U1115

Lost Communication with Tilt & Telescopic Module
  • Multiplex tilt and telescopic ECU branch line or connector
  • Power source circuit of multiplex tilt and telescopic ECU
  • Multiplex tilt and telescopic ECU ground circuit
  • Multiplex tilt and telescopic ECU

HINT:

The main body ECU (multiplex network body ECU) stores DTCs when it detects a communication stop or network communication error for ECUs connected to sub bus 1.

    Fail-safe Chart
    FAIL-SAFE CHART FAIL-SAFE FUNCTION (a) When communication fails in any of the CAN bus lines (communication lines), a fail-safe function(s) will operate. The fail-safe function that is specified for ea ...

    ECU Malfunction (B1003)
    DESCRIPTION DTC No. Detection Item DTC Detection Condition Trouble Area Note B1003 ECU Malfunction The network gateway ECU detects an internal malfunction. Network gateway ECU - ...

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    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Owners Manual

    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Repair Manual

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