Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2003 Lexus LS 430FACTORY OEM SERVICE PROCEDURE
Section 150 (Cruise Control Systems)
WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
- Description
- Operation
- Component Locations
- Adjustments
- Trouble Shooting
- Self-Diagnostic System
- Connector Identification
- Diagnostic Tests
- Notes
- DTC 11: Short In Cruise Control Actuator Circuit Or DTC 15: Open In Cruise Control Actuator Circuit
- DTC 12: Cruise Control Actuator Magnetic Clutch Circuit
- DTC 14: Cruise Control Actuator Mechanical Fault
- DTC 21: Vehicle Speed Sensor Circuit
- DTC 23: Vehicle Speed Sensor Signal Abnormal
- DTC 32: Cruise Control Switch Circuit
- DTC 41: Cruise Control Ecu
- DTC 42: Power Source Voltage Drop
- DTC 51: Idle Signal Circuit
- System Tests
- Notes
- Test No. 1: Set Function Not Occurring Or Cancel Function Occurring (Normal DTC Output On Input Signal Check)
- Test No. 2: Set Function Not Occurring Or Cancel Function Occurring (No DTC Output)
- Test No. 3: Actual Vehicle Speed Deviates From Set Speed
- Test No. 4: Frequent 3RD & Overdrive Gear Shifting (Hunting) While Driving Uphill
- Test No. 5: Cruise Control Does Not Cancel Even When Brake Pedal Is Depressed
- Test No. 6: Cruise Control Does Not Cancel Even When Transaxle Is Shifted To Neutral
- Test No. 7: Cruise Control Switch Does Not Operate (Set/Coast, Res/Acc Or Cancel Functions Not Possible)
- Test No. 8: Set Possible At 25 Mph Or Less, Or Cancel Does Not Operate At 25 Mph Or Less
- Test No. 9: Poor Response In Acc & Res Modes
- Test No. 10: Overdrive Does Not Resume, Even Though Road Is Not Uphill
- Test No. 11: DTC Memory Erased
- Test No. 12: DTC Not Output, Or DTC Output When It Should Not Be
- Test No. 13: Cruise Indicator Light Stays On Or Fails To Turn On
- Component Tests
- Pin Voltage Tests
- Removal & Installation
- Wiring Diagrams
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.