P0E98DC/DC Converter Voltage Sensor C Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P0E98 is set when the C voltage channel of a DC/DC converter is stuck at the lowest end of its range, typically because the measuring line is grounded or the sensing stage has lost its supply. No manufacturer documents P0E98 publicly. GM's 2025 tables (25OBDG03A) show the matching test on channels A and B of the 12 V stabiliser used for auto-starts: below 1 V in 320 out of 400 readings at a 12.5 ms rate gives P0E33 or P0E38, rated Type B. A third channel would be judged the same way. CARB calls for range monitoring of inputs like this. If the converter output itself is normal on the other channels, the fault lies in the C path. The high counterpart is P0E99.
- What you may notice
- MIL on, depending on the manufacturer's rating
- Converter output reduced or switched to a fallback value
- Start-stop or 12 V support may be disabled
- Likely causes
- LikelySensor C signal line shorted to ground
- PossibleMeasuring stage without supply or with an open signal path
- RareInternal defect in the converter's measuring circuit
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €80 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.