Fuel Injector Group Supply Voltage Circuit Low
Code P2147 indicates that the PCM has detected a low voltage condition in the supply circuit for a group of fuel injectors. This typically means the voltage is below the expected threshold, often due to a wiring issue, poor connection, or a failing injector driver. The injector group may be bank-specific (e.g., Bank 1 or Bank 2) depending on the vehicle. Low voltage can cause injectors to not open properly, leading to misfires, poor fuel economy, and potential engine damage if ignored.
1. Most Common Causes
- Open or shorted wiring in the injector group supply circuit
- Faulty fuel injector(s) causing excessive current draw
- Corroded or loose connector at the injector or PCM
- Failed PCM internal injector driver
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine misfire or rough idle
- Reduced engine power and poor acceleration
- Increased fuel consumption
3. Step-by-Step Diagnosis
Step 1: Scan for additional codes and freeze frame data to identify the injector group.
Step 2: Visually inspect wiring and connectors for damage, corrosion, or looseness.
Step 3: Use a multimeter to check voltage at the injector group supply circuit (should be near battery voltage with key on).
Step 4: Test injector resistance and current draw; compare to specifications.
Step 5: If wiring and injectors are good, suspect PCM failure and test injector driver output.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Low voltage can cause injectors to malfunction, leading to misfires, catalytic converter damage, and potential engine stalling. Have it diagnosed promptly.
How much does it cost to fix?▼
Costs vary: simple wiring repair $50-$100, injector replacement $100-$300 per injector, PCM replacement $500-$1000. Diagnosis typically $50-$150.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.