What it means
TPS G above upper plausibility — open signal or short to B+. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Throttle position channel G reports throttle angle to the electronic throttle control module. P212D sets when G rises above its expected range, often because the signal wire is open or is shorted to battery supply.
Common causes
Most likely first.
- Open signal line
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
How to diagnose it
- Check freeze-frame data and live position readings to determine whether the G signal is high continuously or changes with vibration.
- Inspect the G connector for corrosion, loose or pushed-back pins, and moisture that could interrupt the signal path.
- Trace the G signal wire for breaks, pinching, or contact with a battery-supply wire, especially around harness bends and brackets.
- Using the wiring diagram, check G-signal continuity and test for a short to supply with the manufacturer's procedure.
- If the circuit is intact, compare the sensor's G output through throttle movement with the manufacturer's specification.
Common fixes
- Clean and secure poor G-channel connector contacts.
- Repair an open in the G signal wire.
- Repair insulation where the G signal wire contacts a supply wire.
- Replace the throttle position sensor or throttle body if its G signal stays high with a sound circuit.
Can I keep driving?
The module may limit throttle response, and acceleration can become unreliable. Avoid fast roads and overtaking; if the vehicle surges or enters reduced-power mode, stop safely and arrange repair.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.