What does this code mean?
The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.
A code identifies a detected condition, not a part that must automatically be replaced.
Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
P0401Exhaust Gas Recirculation Flow Insufficient DetectedP0401EXHAUST GAS RECIRCULATION FLOW INSUFFICIENT DETECTEDP0401Exhaust Gas Recirculation Flow insufficient DetectedManufacturer communications
15Original wording in English
LEXUS
Reported code forms P0401
TSB: Rev1 Warranty information has been updated. Some 2011 - 2012 CT 200h vehicles may exhibit a vibration due to rough idle and/or tapping noise from HV transaxle at cold start. The Check Engine Light may also…
LEXUS
Reported code forms P0401
TSB: REV1 WARRANTY INFORMATION HAS BEEN UPDATED. SOME 2011 – 2012 CT 200H VEHICLES MAY EXHIBIT A VIBRATION DUE TO ROUGH IDLE AND/OR TAPPING NOISE FROM HV TRANSAXLE AT COLD START. THE CHECK ENGINE LIGHT MAY ALSO…
LEXUS
Reported code forms P0401
Warranty Policy Bulletin (POL16-02): Lexus has received reports of a rough idle and/or rattle noise from the transaxle at cold start due to a sticking Exhaust Gas Recirculation (EGR) Valve in some vehicles. If this…
LEXUS
Reported code forms P0401
Dealer Letter: In these vehicles, Lexus has received some reports of a rough idle and/or rattle noise from the transaxle at cold start due to a sticking Exhaust Gas Recirculation (EGR) Valve. If this occurs, the vehicle…
LEXUS
Reported code forms P0401
Dealer email: In these vehicles, Lexus has received some reports of a rough idle and/or rattle noise from the transaxle at cold start due to a sticking Exhaust Gas Recirculation (EGR) Valve. If this occurs, the vehicle…
LEXUS
Reported code forms P0401
"DEALER LETTER: IN THESE VEHICLES, LEXUS HAS RECEIVED SOME REPORTS OF A ROUGH IDLE AND/OR RATTLE NOISE FROM THE TRANSAXLE AT COLD START DUE TO A STICKING EXHAUST GAS RECIRCULATION (EGR) VALVE. IF THIS OCCURS, THE…
Check vehicle applicability
1A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Lexus | CT HYBRID | 2011 |
Before replacing a part
Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.