P0C3C code meaning
DC/DC Converter Temperature Sensor A Intermittent/Erratic
Powertrain system Generic code P0Cxx codes Check engine light
What P0C3C means
P0C3C covers a signal from DC/DC converter temperature sensor A that drops out or jumps for short moments while staying mostly within range. The heat sink of a converter warms and cools slowly, so fast jumps point to the signal path rather than to real temperature changes. No manufacturer documents P0C3C publicly. The method is known from GM's hybrid tables for comparable thermistors, such as P0C37 for battery sensor F: the controller adds up signal changes in short windows and fails the test when several windows exceed a limit. CARB requires such inputs to be monitored for faults. Typical causes are a loose terminal, vibration damage or moisture at the converter connector. Unlike P0C3A and P0C3B, the fault may vanish between tests, so a wiggle test helps.
P0C3C at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.5 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P0C3C
- Intermittent hybrid or EV warning
- Occasional 12 V charging interruptions
Common causes of P0C3C
- Most likelyLoose terminal or moisture at the converter connector
- PossibleHarness damaged by vibration with intermittent contact
- Less likelyIntermittent fault inside the converter
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Dcdc converter temp sensor aWiring harnessDcdc converter
What each part of P0C3C means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| C | Area: hybrid propulsion. |
| 3C | The exact fault in that area. |
What to do next
- Note P0C3C and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0C3C
What does P0C3C mean?
P0C3C means "DC/DC Converter Temperature Sensor A Intermittent/Erratic". P0C3C covers a signal from DC/DC converter temperature sensor A that drops out or jumps for short moments while staying mostly within range. It is a generic code, so it means the same on every make.
Is it safe to drive with P0C3C?
Drive gently and only to a workshop. With P0C3C the car can go into limp mode (reduced power) to protect itself.
Will P0C3C fail an emissions test?
Yes, it can. P0C3C is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0C3C to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will P0C3C clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.