P216C code meaning
Fuel Injector Group E Supply Voltage Circuit High
Powertrain system Generic code P21xx codes Check engine light
What P216C means
P216C is the opposite fault of group E: the feed of the cylinder 5 injector carries voltage when it should not. GM tests it while the high-side driver is switched off; if 1 V or less remains between the signal and the controller supply, the line is treated as shorted to power. Its 2016 3.6 LGX V6 and 2018 6.2 LT4 V8 tables need at least 11 V and count 10 failures out of 20 samples at 100 ms, type A with the MIL on the first trip. Typical sources are a chafed wire touching another powered circuit or an injector winding contacting a live conductor; GM's PI0631H lists this code with dozens of others for the Impala harness that wears on the transmission. Because the injector may stay energised, the module cuts it off and cylinder 5 drops out. P216B is the short to ground.
P216C at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.8 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P216C
- Check engine lamp on immediately
- Cylinder 5 misfire and rough idle
Common causes of P216C
- Most likelyInjector 5 feed chafed against a powered circuit
- PossibleHigh-side driver in the engine control module leaking voltage
- Less likelyMoisture or corrosion bridging pins in the injector connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Fuel injectorInjector wiringEngine control module
What each part of P216C 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. |
| 6C | The exact fault in that area. |
What to do next
- Note P216C 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 P216C
What does P216C mean?
P216C means "Fuel Injector Group E Supply Voltage Circuit High". P216C is the opposite fault of group E: the feed of the cylinder 5 injector carries voltage when it should not. It is a generic code, so it means the same on every make.
Is it safe to drive with P216C?
Drive gently and only to a workshop. With P216C the car can go into limp mode (reduced power) to protect itself.
Will P216C fail an emissions test?
Yes, it can. P216C 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 P216C to fix?
Difficulty: hard. A typical repair takes 0.8 to 5 hours of work. This is a job for a workshop.
Will P216C clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.