Cruise Control Switch Circuit

2010 Lexus LX 570 V8-5.7L (3UR-FE)SECTION Cruise Control Switch Circuit




CRUISE CONTROL: CRUISE CONTROL SYSTEM: Cruise Control Switch Circuit
- Cruise Control Switch Circuit

DESCRIPTION

The cruise control main switch is used to operate 7 functions: SET, - (COAST), TAP-DOWN, RES (RESUME), + (ACCELERATION), TAP-UP, and CANCEL. The SET, TAP-DOWN and - (COAST) functions, and the RES (RESUME), TAP-UP and + (ACCELERATION) functions are operated with the same switch. The cruise control main switch is an automatic return type switch which turns on only while operating it in each arrow direction and turns off after releasing it. The internal contact point of the cruise control main switch is turned on with the switch operation. Then the ECM reads the resistance value that has been changed by the switch operation to control SET, - (COAST), RES (RESUME), + (ACCELERATION) and CANCEL.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM (CRUISE CONTROL MAIN SWITCH)





(a) Using the Techstream, read the Data List.

Cruise Control





OK:

The Techstream display changes according to operation of cruise control main switch.

NG -- INSPECT CRUISE CONTROL MAIN SWITCH

OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Cruise Control System

2. INSPECT CRUISE CONTROL MAIN SWITCH





(a) Remove the cruise control main switch Removal.

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

Standard Resistance:





NG -- REPLACE CRUISE CONTROL MAIN SWITCH Removal
OK -- Continue to next step.

3. INSPECT CRUISE CONTROL SWITCH WIRE





(a) Remove the cruise control switch wire.

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

Standard Resistance:





NG -- REPLACE CRUISE CONTROL SWITCH WIRE
OK -- Continue to next step.

4. INSPECT SPIRAL CABLE





(a) Check the spiral cable and connector for scratches, cracks, dents and chips. If any defects are found, replace the spiral cable with a new one.

(b) Check the spiral cable.

(1) Set the spiral cable to the center position Removal.

(2) After setting the spiral cable to the center position, rotate the spiral cable 2.5 times clockwise, and measure the resistance according to the value(s) in the table below. Then rotate the spiral cable 5 times counterclockwise, and measure the resistance according to the value(s) in the table below.

Standard Resistance:





(3) After setting the spiral cable to the center position, rotate the spiral cable 2.5 times clockwise. Then while rotating the spiral cable 5 times counterclockwise, measure the resistance according to the value(s) in the table below.

NOTICE:
As the spiral cable may break, do not rotate the spiral cable more than the specified amount.

Standard Resistance:





NG -- REPLACE SPIRAL CABLE Removal
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (SPIRAL CABLE - ECM AND BODY GROUND)





(a) Disconnect the E12 spiral cable connector.

(b) Disconnect the A38 ECM connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE ECM Removal
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.