DYNAMIC RADAR CRUISE CONTROL SYSTEM, Diagnostic DTC:C1A05

DTC Code DTC Name
C1A05 Stop Light Switch Circuit

DESCRIPTION

When the brake pedal is depressed, the stop light switch assembly sends a brake pedal operation signal to the driving support ECU assembly. After reception of this signal, the driving support ECU assembly cancels the dynamic radar cruise control system. When the driving support ECU assembly detects a problem in the stop light switch assembly circuit, DTC C1A05 is stored.

DTC No. Detection Item DTC Detection Condition Trouble Area
C1A05 Stop Light Switch Circuit When the power switch is on (IG) and the dynamic radar cruise control system is turned on using the cruise control main switch (ON/OFF button), the driving support ECU assembly detects a malfunction in the signal from the stop light switch circuit.

  • Stop light switch assembly

  • Harness or connector

  • Driving support ECU assembly

WIRING DIAGRAM

B004EO8E07

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses for circuits related to this system before performing the following procedure.

  • When replacing the driving support ECU assembly, always replace it with a new one. If a driving support ECU assembly which was installed to another vehicle is used, the information stored in the driving support ECU assembly will not match the information from the vehicle. As a result, a DTC may be stored.

PROCEDURE


  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF STOP LIGHT SWITCH ASSEMBLY)


    1. B004FUQC61
      *a

      Front view of wire harness connector

      (to Stop Light Switch Assembly)

      Disconnect the A52 stop light switch assembly connector.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A52-1 (B) - Body ground Always 11 to 14 V
      A52-5 (B) - Body ground Power switch on (IG) 11 to 14 V
      Standard Resistance
      Tester Connection Condition Specified Condition
      A52-3 (GND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. INSPECT STOP LIGHT SWITCH ASSEMBLY


    1. Inspect the stop light switch assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE STOP LIGHT SWITCH ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (DRIVING SUPPORT ECU ASSEMBLY - STOP LIGHT SWITCH ASSEMBLY)


    1. Disconnect the Q2 driving support ECU assembly connector.

    2. Disconnect the A52 stop light switch assembly connector.

    3. Disconnect the A13 certification ECU (smart key ECU assembly) connector.

    4. Disconnect the A23 skid control ECU assembly connector.

    5. Disconnect the O45 transmission floor shift assembly (shift lock control unit) connector.

    6. Disconnect the 1D stop light relay (semiconductor power integration ECU) connector.

    7. Disconnect the A80 and A81 hybrid vehicle control ECU assembly connector.

    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      Q2-15 (STP-) - A52-2 (L) Always Below 1 Ω
      Q2-1 (ST1-) - A52-4 (L) Always Below 1 Ω
      Q2-15 (STP-) or A52-2 (L) - Body ground Always 10 kΩ or higher
      Q2-1 (ST1-) or A52-4 (L) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE DRIVING SUPPORT ECU ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR