P040D on Toyota
Exhaust Gas Recirculation Temperature Sensor "A" Circuit High
P040D on Toyota vehicles indicates exhaust gas recirculation temperature sensor "a" circuit high. Au7o has documented this code across 1 Toyota model — most commonly on RAV4. This code means the engine computer detected an abnormally high voltage on the circuit for EGR temperature sensor 'A'. This sensor measures the temperature of exhaust gases moving through the EGR system (often around the EGR cooler) to confirm the system is flowing and to protect components from overheating. A high-circuit reading usually points to a sensor or wiring problem rather than an actual overheat. It typically triggers the check engine light and may affect emissions and EGR operation. Typical repair costs on Toyota range from $350 to $1,500, depending on the specific model and root cause.
Common Causes of P040D
- •Faulty EGR temperature sensor (sensor A)
- •Open circuit or broken wire in the sensor circuit
- •Corroded, loose, or disconnected connector
- •Wiring shorted to a high-reference voltage
- •Poor sensor ground
- •Failing PCM/ECM (rare)
P040D on Toyota by Model
Toyota RAV4(1 issue)
- Hybrid EGR Cooler/Valve Clogging and Coolant Leak on A25A-FXS 2.5L (White Smoke, Power Loss)2019-2025
The Dynamic Force A25A-FXS 2.5L hybrid uses a water-cooled EGR (exhaust gas recirculation) cooler and valve to lower combustion temperatures for efficiency. On the XA50 RAV4 Hybrid, the EGR cooler is prone to two failure modes: internal coolant leakage (coolant gets into the exhaust/intake, producing clouds of white smoke and slowly drinking coolant), and heavy soot/tar packing of the cooler passages and EGR valve that clogs the system. Owners and teardown reports document the EGR system becoming caked with carbon by roughly 60k-80k miles, and a stuck or clogged valve causes rough running, hesitation, and noticeable power loss. The condition can also throw EGR-related check-engine codes. It is a high-search hybrid-specific concern because it affects the most popular powertrain in the lineup and the repair is labor-intensive.
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View P040D across all makes →Frequently Asked Questions
What does P040D mean on Toyota?▼
P040D stands for "Exhaust Gas Recirculation Temperature Sensor "A" Circuit High." This code means the engine computer detected an abnormally high voltage on the circuit for EGR temperature sensor 'A'. This sensor measures the temperature of exhaust gases moving through the EGR system (often around the EGR cooler) to confirm the system is flowing and to protect components from overheating. A high-circuit reading usually points to a sensor or wiring problem rather than an actual overheat. It typically triggers the check engine light and may affect emissions and EGR operation. On Toyota specifically, this code is documented across 1 model.
What causes P040D on Toyota vehicles?▼
Common causes on Toyota: Faulty EGR temperature sensor (sensor A), Open circuit or broken wire in the sensor circuit, Corroded, loose, or disconnected connector, Wiring shorted to a high-reference voltage, Poor sensor ground. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P040D on a Toyota?▼
Repair costs on Toyota range from $350 to $1,500, depending on the specific model and root cause.
Which Toyota models have P040D documented?▼
Au7o has documented P040D on 1 Toyota model: RAV4.