Fuel Injector Group Supply Voltage Circuit High
The P216C code indicates that the powertrain control module (PCM) has detected a voltage level in the fuel injector group supply circuit that is higher than the specified range. This circuit provides power to a group of fuel injectors, and an overvoltage condition can result from a faulty voltage regulator, a short to voltage in the wiring, or a malfunctioning PCM. High voltage can cause injectors to stay open longer than intended, leading to rich fuel mixture, misfires, and potential engine damage.
1. Most Common Causes
- Faulty voltage regulator or alternator overcharging
- Short to battery voltage in the injector group supply circuit
- Corroded or damaged wiring/connectors
- Faulty PCM (rare)
2. Symptoms You Will Notice
- Check Engine Light on
- Engine misfire or rough idle
- Poor fuel economy
- Black smoke from exhaust (rich condition)
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm the code and check for related codes (e.g., P216B, P216D).
Step 2: Inspect the fuel injector group supply circuit wiring and connectors for damage, corrosion, or shorts to voltage.
Step 3: Measure voltage at the injector group supply circuit with the engine running; compare to manufacturer specifications (typically 12-14V).
Step 4: Test the alternator output voltage to rule out overcharging.
Step 5: If wiring and alternator are okay, test the PCM for proper operation or check for software updates.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not recommended. High voltage can damage fuel injectors and the catalytic converter, and may cause drivability issues like stalling or misfires.
How much does it cost to fix?▼
The cost varies depending on the cause. Wiring repairs can be $150-$300, while replacing a PCM can cost $400-$800 or more.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.