Vehicle Speed Sensor Circuit Failure
There's a problem with the vehicle speed sensor circuit.
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 vehicle speed sensor reports how fast the car is going. If this sensor or its circuits fail, the computer can't tell how fast it's moving, which can mess with your speedometer and other systems.
What the computer is actually seeing
The Engine Control Module (ECM) relies on the vehicle speed sensor to receive a signal that represents vehicle speed. When the signal is missing or erroneous, it triggers code C1167.
What a healthy reading looks like
The vehicle speed sensor should produce 0-5 volts (typically around 2.5V at idle) depending on the speed of the vehicle.
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.
- 1Check the vehicle speed sensor connector for damage or corrosion. Repair if needed and retest.
- 2Measure the voltage at the vehicle speed sensor while the vehicle is moving. It should vary between 0-5 volts. If not, the sensor may be faulty.
- 3Inspect the wiring between the sensor and the ECM for breaks or shorts. Fix any issues discovered.
- 4If the sensor tests good and the wiring is intact, consider testing or replacing the ECM.
Common causes
- Faulty vehicle speed sensor
- Damaged wiring or connectors
- Corrosion in the connector
- Faulty ECM or control module
Typical repair cost
$$
Related codes
Frequently asked questions
Can I drive my vehicle with this code?
It's not safe to drive. Speed-related systems may fail, risking your safety.
Will this code come back after clearing?
If the underlying issue isn't fixed, it will likely reappear.
Why does this code pair with C1166?
Both codes relate to issues in the vehicle speed sensor circuit, indicating similar or related problems.
Working a real vehicle right now?
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