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.
2008 Lexus IS FFACTORY OEM SERVICE PROCEDURE
Power Assist Systems
- Power Steering System
- Precaution
- Parts Location
- System Diagram
- System Description
- How To Proceed With Troubleshooting
- Calibration
- Problem Symptoms Table
- Terminals Of Ecu
- Diagnosis System
- DTC Check/Clear
- Freeze Frame Data
- Fail-Safe Chart
- Data List / Active Test
- Diagnostic Trouble Code Chart
- On-Vehicle Inspection
- DTC C1511: Torque Sensor Circuit Malfunction; DTC C1512 Torque Sensor Circuit Malfunction; DTC C1513 Torque Sensor Circuit Malfunction
- DTC C1515: Torque Sensor Zero Point Adjustment Undone; DTC C1525 Rotation Angle Sensor Initialization Undone
- DTC C1516: Torque Sensor Zero Point Adjustment Incomplete; DTC C1526 Rotation Angle Sensor Initialization Incomplete
- DTC C1521: Motor Circuit Malfunction; DTC C1522 Motor Circuit Malfunction; DTC C1523 Motor Circuit Malfunction; DTC C1524 Motor Circuit Malfunction; DTC C1532 ECU Malfunction; DTC C1555 Motor Relay Welding Failure
- DTC C1528: Motor Rotation Angle Sensor Malfunction
- DTC C1531: ECU Malfunction; DTC C1533: ECU Malfunction; DTC C1534: ECU Malfunction
- DTC C1541: Vehicle Speed Signal Malfunction
- DTC C1551: IG Power Supply Voltage Malfunction
- DTC C1552: PIG Power Supply Voltage Malfunction; DTC C1554: Power Supply Relay Failure
- DTC C1581: Assist Map Number Un-Writing
- DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0129: Lost Communication with Brake System Control Module
- PS Warning Light Remains ON
- PS Warning Light does not Come ON
- Power Steering Ecu
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.