P212C code meaning
Throttle Position Sensor/Switch G Circuit Low
Powertrain system Generic code P21xx codes Check engine light
What P212C means
P212C sets when position signal G reads below its lower electrical limit. The letter G only comes into play on engines with more than one electronic throttle. GM's 2023 and 2024 OBD tables (23OBDG07, 24OBDG07) give it to the second position sensor in the bank 2 throttle body of a twin-throttle engine: a raw voltage under 0.195 V lasting 0.14 s while the ECU is running stores the code within one trip. Usual culprits are a signal wire shorted to ground, a lost 5 V feed to that throttle body or a damaged sensor track. P212D is the matching high fault, P212A the general circuit code, P212B the plausibility check of G. Once a bank 2 signal is lost, the ECU typically restricts power.
P212C at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P212C
- Engine warning lamp on
- Reduced engine power message
- Uneven idle or hesitation on one bank
Common causes of P212C
- Most likelySignal wire of sensor G shorted to ground
- Possible5 V reference to the bank 2 throttle body open or pulled low
- PossibleWorn or damaged track of position sensor G inside the throttle body
- Less likelyCorroded or loose terminals at the bank 2 throttle connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Throttle position sensor gElectronic throttle body
What each part of P212C means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 1 | Area: fuel and air metering. |
| 2C | The exact fault in that area. |
What to do next
- Note P212C 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 P212C
What does P212C mean?
P212C means "Throttle Position Sensor/Switch G Circuit Low". P212C sets when position signal G reads below its lower electrical limit. It is a generic code, so it means the same on every make.
Is it safe to drive with P212C?
Drive gently and only to a workshop. With P212C the car can go into limp mode (reduced power) to protect itself.
Will P212C fail an emissions test?
Yes, it can. P212C 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 P212C to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P212C clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.