4 Pin Cruise Control pinout | Lexus V8 Engines LLC

Overview

The 4-pin cruise control client plug separates the cruise control wiring from the main engine and transmission client plugs. This makes the vehicle-side cruise circuits easier to test and service.

The plug provides two brake switch inputs, the cruise control lever signal, and a cruise indicator light circuit where applicable.

Important

This guide covers the vehicle-side 4-pin cruise control client plug only. The standalone harness provides the cruise-related interface circuits, but the installer must still wire the brake switch, cruise lever, and dash indicator correctly for the receiving vehicle.

General Information Notice

This document is provided for general information and customer reference only. Final wiring must be verified against the exact harness supplied and the vehicle-side circuit being connected.

Quick Start: Critical Connections

Function Group	Circuit / Pin	Wire(s)	Customer Connection
Brake Switch N/O	STP	Pin 1	Connect to the normally open brake switch circuit. This changes state when the brake pedal is applied.
Cruise Lever	CCS	Pin 2	Connect to the compatible cruise control lever/switch signal circuit.
Cruise Indicator	PI	Pin 3	Connect to the dash cruise indicator light where applicable.
Brake Switch N/C	ST1-	Pin 4	Connect to the normally closed brake switch circuit. This should change state opposite STP.

Wire Color / Tracer Reference

Stripe/tracer colors are shown as diagonal bands on the wire. The first color is the base wire color. The second color is the stripe/tracer color.

Yellow / WhiteYellow base wire with White tracer

Yellow / OrangeYellow base wire with Orange tracer

GreenGreen solid wire

Yellow / BlueYellow base wire with Blue tracer

Full Pinout Reference

Pin	Wire Visual	Circuit / Function	Signal Type	Notes
Pin 1	Yellow / White	STP	Brake switch normally open input	Connect to the normally open brake switch circuit. This is the brake-applied signal used by ECU/cruise logic.
Pin 2	Yellow / Orange	CCS	Cruise control lever signal	Connect to the cruise lever/switch signal. Confirm lever type and resistor/switch strategy before connecting.
Pin 3	Green	PI	Cruise control indicator light	Connect to the cruise dash indicator light where applicable. Low-current indicator only.
Pin 4	Yellow / Blue	ST1-	Brake switch normally closed input	Used as the second brake switch/cruise cancel confirmation input. Must change state opposite STP.

Detailed Circuit Notes

Brake switch circuits

Identify the normally open and normally closed brake switch circuits with a meter before connecting.
With the brake released, one brake circuit should be closed while the other is open. When the brake is pressed, they should swap state.
Do not join STP and ST1- together. They are separate safety and logic inputs.

Cruise lever signal

Confirm the cruise lever is compatible with the ECU/cruise strategy being used.
Do not apply direct power to CCS unless the build-specific wiring diagram calls for it.
Verify ON/OFF, SET/COAST, RES/ACC, and CANCEL commands with scan data or electrical testing when possible.

Indicator light

Confirm whether the cluster expects ground-side control or positive feed.
Use a low-current lamp or LED with proper current limiting.
Do not use the PI circuit to power relays or high-current lights.

First Test Checklist

Item	Check
Brake release	STP and ST1- show opposite states.
Brake applied	STP and ST1- swap state cleanly.
Cruise lever	Commands are visible with scan data or verified electrically.
Indicator	PI operates the cruise indicator with correct polarity.

Troubleshooting Quick Reference

Symptom	Items to Check
Cruise will not set	Check STP/ST1- states, CCS lever compatibility, and brake light operation.
Cruise cancels immediately	ST1- or STP may be wired incorrectly or showing the wrong state.
Indicator does not light	Check PI polarity, lamp feed, LED resistor, and cluster wiring.

4-Pin Cruise Control Client Plug Guide

Build-Specific Confirmation

Connector Visuals