Engine Coolant Temperature Sensor Voltage High
This code indicates that the engine coolant temperature sensor is reporting a voltage that is higher than normal.
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 engine's coolant temperature sensor measures how hot the coolant is. If it sends out a voltage that doesn't match the expected range, like over 4.8 volts when it should be between 0.5 to 4.5 volts, the computer thinks there's a problem.
What the computer is actually seeing
The engine control module (ECM) expects a voltage signal from the coolant temperature sensor. This signal ranges from about 0.5 volts (cold) to 4.5 volts (hot). If the ECM reads a sustained voltage over 4.8 volts, it triggers this code.
What a healthy reading looks like
0.5 to 4.5 volts at the coolant temperature sensor output under typical operating conditions.
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.
- 11. Check the connector at the coolant temperature sensor. Look for corrosion or loose connections. Repair as necessary. Decision: If the connector looks good, proceed to step 2; if not, repair or replace the connector.
Common causes
- Faulty coolant temperature sensor
- Wiring issues such as shorts or opens
- Corroded or loose connector terminals
- Faulty ECM
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not advisable to drive long distances; the engine might overheat or run inefficiently.
Will this code come back after resetting?
If the underlying issue isn't fixed, yes, the code will likely return.
Why does this code appear with other codes?
Often, wiring issues or a failing ECM can cause multiple related codes.
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