SFI SYSTEM, Diagnostic DTC:P0812

DTC Code DTC Name
P0812 Reverse Input Circuit

DESCRIPTION

The back-up light switch assembly is mounted on the manual transaxle. The switch is turned on when selecting the shift lever in reverse position, and transmits a signal to the ECM.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0812

Reverse Input Circuit

Abnormal back-up light switch assembly signal input to ECM.

  • Back-up light switch assembly

  • Wire harness or connector

  • ECM

Does not come on

DTC stored

MONITOR DESCRIPTION

This DTC is stored when a malfunction is detected in the back-up light switch assembly circuit. If the back-up light switch assembly signal is not received when the vehicle is in reverse, the ECM will store this DTC.

WIRING DIAGRAM

A327741E01

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

  1. INSPECT BACK-UP LIGHT SWITCH ASSEMBLY

    1. Inspect the back-up light switch assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE BACK-UP LIGHT SWITCH ASSEMBLY

    Click here

    OK

  2. CHECK SWITCH INSTALLATION (BACK-UP LIGHT SWITCH ASSEMBLY)

    1. Check the back-up light switch assembly installation.

      OK

      The switch is installed correctly.

    Result

    Proceed to

    OK

    NG
    NG

    SECURELY REINSTALL BACK-UP LIGHT SWITCH ASSEMBLY

    Click here

    OK

  3. CHECK TERMINAL VOLTAGE (POWER SOURCE OF BACK-UP LIGHT SWITCH ASSEMBLY)

    A340587C01

    *a

    Front view of wire harness connector

    (to Back-up Light Switch Assembly )

    1. Disconnect the back-up light switch assembly connector.

    2. Turn the ignition switch to ON.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      C5-1 - Body ground

      Ignition switch ON

      11 to 14 V

    Result

    Result

    Proceed to

    OK

    A

    NG (w/ Entry and Start System)

    B

    NG (w/o Entry and Start System)

    C
    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BACK-UP LIGHT SWITCH ASSEMBLY - IG1 RELAY)

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BACK-UP LIGHT SWITCH ASSEMBLY - IGNITION SWITCH ASSEMBLY)

    A

  4. CHECK HARNESS AND CONNECTOR (BACK-UP LIGHT SWITCH ASSEMBLY - ECM)

    1. Disconnect the back-up light switch assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      C5-2 - B56-3 (R)

      Always

      Below 1 Ω

      C5-2 or B56-3 (R) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE ECM

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR