Toyota & Lexus
OBD codes explained
The codes Toyota and Lexus owners actually see — VVT, throttle, catalysts and EVAP — with clear causes and fixes.
Toyota / Lexus check engine light codes
Toyota and Lexus use standard OBD-II engine codes, readable by any scanner. Toyota’s Techstream adds module depth, but most engine codes are fully readable generically.
Here are the codes most reported on Camry, Corolla, RAV4, Hilux and Lexus models.
OBD-II code decoder
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Most common Toyota / Lexus
Classic Toyota/Lexus faults behind these codes.
| Code | Description |
|---|---|
| P0012 | "A" Camshaft Position Timing Over-Retarded (Bank 1) |
| P0128 | Coolant Thermostat Below Regulating Temperature |
| P0171 | System Too Lean (Bank 1) |
| P0300 | Random/Multiple Cylinder Misfire |
| P0420 | Catalyst System Efficiency Below Threshold (Bank 1) |
| P0442 | EVAP System Small Leak Detected |
| P0446 | EVAP Vent Control Circuit Malfunction |
| P2118 | Throttle Actuator Motor Range |
Common Toyota / Lexus faults
Classic Toyota/Lexus faults behind these codes.
VVT timing over-retarded (P0012) — low oil or a clogged VVT oil control valve, common on VVT-i engines.
Throttle actuator (P2118) — carbon-clogged throttle body on electronic-throttle models.
Catalyst efficiency (P0420) — an aging converter, especially on high-mileage models.
EVAP leaks (P0442/P0446) — fuel cap, vent valve or charcoal canister.
Thermostat (P0128) — stuck-open thermostat on many models.
Toyota / Lexus FAQ
What causes P0012 on a Toyota?
Is P2118 a big repair?
Why does my Toyota show P0420?
Are Toyota and Lexus codes the same?
Can I clear the code and pass inspection?
Codes vary slightly by model, year and engine. Always confirm with a proper diagnosis. Manufacturer-specific codes (P1xxx/P2xxx) may differ from generic descriptions.
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Decode your Toyota / Lexus code now
Use the free decoder below, or browse the most common Toyota / Lexus codes.