P0C3B: DC/DC Converter Temperature Sensor A High
What to do
As P0C38.
What this code means
DC/DC converter temperature sensor A is reading above its valid range, which is an instrument fault rather than a genuinely overheating converter. What the converter does, and why its faults are mistaken for a failing 12-volt battery, are at P0C38.
Likely causes
Start here
- Faulty DC-DC converter · specialist
- Corroded or loose connector · easy
Less common
- Low inverter coolant level · easy
- Air trapped in the inverter cooling circuit · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
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