P0698Sensor Reference Voltage C Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- The engine module feeds sensors from several regulated 5 V reference circuits; a short at one sensor pulls the whole circuit down, so all its sensors report at once – unplug them one by one to find the culprit. Which sensors hang on circuit C depends on the maker – pedal sensor 2 is common to all: GM 2016–2025 feeds only pedal sensor 2 from it, the Saab 9-4X also the MAP sensor, the Saab 9-5 2.0 L turbo also throttle, crankshaft and A/C pressure sensors, and Bentley's 2026 Bentayga V8 lists its own set. P0698 means reference C is too low – usually a short to ground. GM's 6.6 L Duramax LB7/LLY sets it below 4.7 V for 2 s, GM Europe's 2.0 L turbo after 1 s or 10 s cumulative, each with the lamp in the first trip; newer GM engines report it as P0697.
- What you may notice
- Check engine light
- Several sensor codes at once (pedal, throttle, pressure)
- Electronic throttle limp mode, reduced power
- Possibly starting problems
- Likely causes
- LikelyShort in the wire or sensor of a connected sensor
- PossibleChafing or water in harness or connector
- PossibleA connected sensor faulty internally
- RareModule internal voltage regulator
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.