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SPN 4395moderate severity✨ AI-generated

Exhaust Gas Temperature Sensor 1 Circuit High

The exhaust gas temperature sensor is reporting a high voltage anomaly.

Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.

What it means (plain English)

The exhaust gas temperature sensor measures how hot the exhaust gases are as they're released from the engine. If the reading is too high, it could indicate the sensor is malfunctioning or there's a wiring issue.

What the computer is actually seeing

The engine control unit (ECU) expects a voltage signal typically between 0.5V and 1.5V from the exhaust gas temperature sensor. A voltage above this range indicates a fault.

What a healthy reading looks like

Normal operating voltage for the exhaust gas temperature sensor should be between 0.5V (cold) and 1.5V (operating temperature).

Guided diagnostic — the DiagCoach way

Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.

  1. 1Check exhaust gas temperature sensor wiring for damage or shorts. Repair any issues found.
  2. 2Inspect connectors at the exhaust gas temperature sensor and ECM for corrosion or loose connections. Fix as necessary.
  3. 3Test the exhaust gas temperature sensor with a multimeter. Measure the voltage during engine operation. Is it above 1.5V? If yes, replace the sensor.
  4. 4If the voltage is within normal range, check the ECM for fault codes related to other sensors, as issues might be linked.

Common causes

  • Shorted wire in the sensor circuit
  • Faulty exhaust gas temperature sensor
  • Open circuit in the wiring harness
  • Poor electrical connection at the sensor or ECM connector

Typical repair cost

$$

Related codes

Frequently asked questions

Can I drive the vehicle with this code?

It's drivable but you should address the issue soon, as prolonged high exhaust gas temperatures can damage engine components.

Will this code come back after replacing the sensor?

If the sensor replacement is successful and no wiring issues exist, the code should not return.

Why might this code appear with other codes?

Sharing similar circuits or systems can trigger multiple codes, especially if there's an electrical issue affecting more than one sensor.

Working a real vehicle right now?

Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.

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