Toyota Tundra Service Manual: Automatic Disconnecting Differential Motor Limit Switch Circuit (P17A4)

Toyota Tundra Service Manual / Engine, Hybrid System / Wf1am Transfer / Touch Select 2-4 And High-low System / Automatic Disconnecting Differential Motor Limit Switch Circuit (P17A4)

DESCRIPTION

When the A.D.D. actuator is switching between 2WD and 4WD, the DL1 and DL2 terminals of the limit switch are in one of the ON/OFF combinations listed in the table below.

Terminal

In 2WD

Switching between 2WD and 4WD

In 4WD

DL1

OFF (OPEN)

ON (GND)

ON (GND)

DL2

ON (GND)

ON (GND)

OFF (OPEN)

This DTC is detected when the limit switch ON/OFF combination (2 lines) is abnormal.

DTC Code

DTC Detection Condition

  1. Diagnosis Condition
  2. Malfunction Status
  3. Malfunction Time
  4. Other

Trouble Area

P17A4
  1. Ignition switch is ON and engine is running
  2. Limit switch DL1 terminal is OFF (OPEN) and the DL2 terminal is OFF (OPEN)
  3. 1 second or more
  4. 1 trip detection logic
  • Wire harness and connector
  • 4 wheel drive control ECU
  • A.D.D. actuator (differential vacuum actuator assembly)

WIRING DIAGRAM

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (4 WHEEL DRIVE CONTROL ECU - DIFFERENTIAL VACUUM ACTUATOR ASSEMBLY)

(a) Disconnect the A25 4 wheel drive control ECU connector.

(b) Disconnect the G1 A.D.D. actuator (differential vacuum actuator assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A25-7 (DL1) - G1-6 (DL1)

Always

Below 1 Ω

A25-20 (DL2) - G1-5 (DL2)

Always

Below 1 Ω

G1-4 (GND) - Body ground

Always

Below 1 Ω

A25-7 (DL1) or G1-6 (DL1) - Body ground

Always

10 kΩ or higher

A25-20 (DL2) or G1-5 (DL2) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

2.

INSPECT DIFFERENTIAL VACUUM ACTUATOR ASSEMBLY (LIMIT SWITCH)

(a) Disconnect the G1 A.D.D. actuator (differential vacuum actuator assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

6 (DL1) - Body ground

Always

10 kΩ or higher

5 (DL2) - Body ground

Always

10 kΩ or higher
Text in Illustration

*a

Component without harness connected

(A.D.D. Actuator [Differential Vacuum Actuator Assembly])
OK

REPLACE DIFFERENTIAL VACUUM ACTUATOR ASSEMBLY

NG

REPLACE 4 WHEEL DRIVE CONTROL ECU

    Automatic Disconnecting Differential Motor Control Circuit High (P17A2)

    Transfer Synchronization Actuator Circuit Open (P17A5,P17A6)

    See More:

    Toyota Tundra Service Manual > Front Shock Absorber: Removal
    REMOVAL CAUTION / NOTICE / HINT HINT: Use the same procedures for the RH side and LH side. The procedures listed below are for the LH side. PROCEDURE 1. REMOVE FRONT WHEEL 2. REMOVE FRONT SHOCK ABSORBER WITH COIL SPRING LH (a) Remove the nut and bolt from the shock absorber lower side. NOTICE: To pr ...

    Toyota Tundra Owners Manual

    Toyota Tundra Service Manual

    © 2025 Copyright www.ttundra.com
    0.0357