Toyota 4Runner Quiz
Vehicle Exterior

Speed Signal Circuit

In this manual: Vehicle Exterior
General — 25Audio / Visual / Telematics — 283Brake — 187Drivetrain — 204Power Source / Network — 79Steering — 76Suspension — 130Vehicle Exterior — 391Vehicle Interior — 693
~1min read
DESCRIPTION

The vehicle speed signal consists of pulses sent to the side auto step controller ECU assembly from the main body ECU (multiplex network body ECU).

WIRING DIAGRAM
PROCEDURE

  1. INSPECT MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)


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

Standard Voltage:

Tester Connection

Condition

Specified Condition

A42-11 (SP1+) - Body ground

Vehicle speed at lower than 8 km/h

11 to 14 V

Vehicle speed at 8 km/h or more

Below 1 V
Text in Illustration

*a

Component with harness connected

(Side Auto Step Controller ECU Assembly)

Result

Proceed to

NG

A

OK

B

B

REPLACE SIDE AUTO STEP CONTROLLER ECU ASSEMBLY
A

  1. CHECK HARNESS AND CONNECTOR (SIDE AUTO STEP ECU - MAIN BODY ECU)

(a) Disconnect the A42 side auto step controller ECU assembly connector.

(b) Disconnect the F9 main body ECU (multiplex network body ECU) connector.

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

Standard Resistance (Check for Open):

Tester Connection

Condition

Specified Condition

A42-11 (SP1+) - F9-15 (SPD)

Always

Below 1 Ω

Standard Resistance (Check for Short):

Tester Connection

Condition

Specified Condition

A42-11 (SP1+) - Body ground

Always

10 kΩ or higher

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

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