Dtc P0812 Reverse Input Circuit

Drivetrain. Land Cruiser. Urj200, 202 Grj200 Vdj200
Ae80F Automatic Transmission Transaxle. Land Cruiser. Urj200, 202 Grj200 Vdj200

DESCRIPTION

MONITOR DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK PARK/NEUTRAL POSITION SWITCH ASSEMBLY (POWER SOURCE)

INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY

CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH ASSEMBLY - TCM)

DTC P0812 Reverse Input Circuit


DESCRIPTION

The park/neutral position switch detects the shift lever position and sends signals to the TCM.

DTC No.
DTC Detection Condition
  1. Diagnosis Condition
  2. Malfunction Status
  3. Malfunction Time
  4. Other
Trouble Area
P0812
  1. Battery voltage is 9.5 V or higher, shift lever in R and DTC P0705 is not detected
  2. R terminal voltage is low
  3. 5 times
  4. 1-trip detection logic
  1. Open or short in park/neutral position switch assembly circuit
  2. Park/neutral position switch assembly
  3. TCM
  1. Battery voltage is 9.5 V or higher, shift lever in D and DTC P0705 is not detected
  2. R terminal voltage is high
  3. 5 times
  4. 1-trip detection logic
  1. Short in park/neutral position switch assembly circuit
  2. Park/neutral position switch assembly
  3. TCM

MONITOR DESCRIPTION

This DTC indicates a problem the park/neutral position switch assembly or the wire harness in the park/neutral position switch assembly circuit.
The park/neutral position switch assembly detects the shift lever position and sends signals to the TCM.
For safety, the park/neutral position switch assembly detects the shift lever position so that the engine can be started only when the shift lever is in P or N.
The park/neutral position switch assembly sends signals to the TCM according to the shift lever position (P, N, R or D).
The TCM determines that there is a problem with the switch or related parts if it receives an R position signal when the shift lever is in D or it does not receives an R position signal when the shift lever is in R. The TCM stores the DTC.

WIRING DIAGRAM

Refer to DTC P0705 (Click here).

INSPECTION PROCEDURE

NOTICE:
  1. Perform registration and/or initialization when parts related to the automatic transmission are replaced (Click here).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
After performing repair, clear the DTCs and perform the following procedure to check that DTCs are not output.
  1. Turn the engine switch on (IG).
  2. Wait for 5 seconds or more with the shift lever in D.
  3. Wait for 5 seconds or more with the shift lever in R.
  4. Check for DTCs again (Click here).
1.CHECK PARK/NEUTRAL POSITION SWITCH ASSEMBLY (POWER SOURCE)


    Land Cruiser. Urj200, 202 Grj200 Vdj200.Ae80F Automatic Transmission Transaxle.Automatic Transmission System. Dtc P0812 Reverse Input Circuit

  1. Disconnect the park/neutral position switch assembly connector.

  1. Turn the engine switch on (IG).

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    C24-1 (RB) - Body ground
    		Engine switch on (IG)
    		11 to 14 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Park/Neutral Position Switch Assembly)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (PARK/NEUTRAL POSITION SWITCH ASSEMBLY - BATTERY)
OK


2.INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY


    Land Cruiser. Urj200, 202 Grj200 Vdj200.Ae80F Automatic Transmission Transaxle.Automatic Transmission System. Dtc P0812 Reverse Input Circuit

  1. Disconnect the park/neutral position switch assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1 (RB) - 2 (RL)
    		Shift lever in R
    		Below 1 Ω
    1 (RB) - 2 (RL)
    		Shift lever not in R
    		10 kΩ or higher
    3 (B) - 2 (RL)
    		Shift lever in P, R, N, D and S
    		10 kΩ or higher
    6 (IG) - 2 (RL)
    		Shift lever in P, R, N, D and S
    		10 kΩ or higher
    Text in Illustration
    *a
    		Component without harness connected
    (Park/Neutral Position Switch Assembly)


NG
REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY (Click here)
OK


3.CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH ASSEMBLY - TCM)

  1. Disconnect the C24 park/neutral position switch assembly connector.

  1. Disconnect the A82 TCM connector.

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

    Standard Resistance:

    Tester Connection
    		Condition
    		Specified Condition
    C24-2 (RL) - A82-5 (R)
    		Always
    		Below 1 Ω
    C24-2 (RL) or A82-5 (R) - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE TCM (Click here)