Fuel Injector Control Module Relay Circuit Malfunction
The P0612 code indicates a fault in the fuel injector control module relay circuit. This relay supplies power to the fuel injector control module, which manages injector timing and fuel delivery. When the powertrain control module (PCM) detects an open, short, or excessive resistance in the relay control circuit, it sets this code. Common causes include a faulty relay, wiring issues, or a defective fuel injector control module. Symptoms may include engine misfires, hard starting, poor fuel economy, and in severe cases, the engine may not start.
1. Most Common Causes
- Faulty or damaged Fuel Injector Control Module (FICM) relay
- Open circuit, short to ground, or short to voltage in the FICM relay control wiring
- Loose, corroded, or high-resistance electrical connections in the relay circuit
- Blown fuse in the FICM power supply circuit
- Internally defective Fuel Injector Control Module (FICM)
- Intermittent or permanent Powertrain Control Module (PCM) failure
2. Symptoms You Will Notice
- Engine misfire or rough idle
- Hard starting or no start condition
- Decreased fuel economy
- Check Engine Light illuminated
- Engine stalling
3. Step-by-Step Diagnosis
Step 1: Scan for other codes and note freeze frame data.
Step 2: Visually inspect the fuel injector control module relay and its wiring for damage, corrosion, or loose connections.
Step 3: Test the relay operation using a multimeter (check coil resistance and continuity).
Step 4: Check for battery voltage and ground at the relay socket with the ignition on.
Step 5: If relay and wiring are okay, test the fuel injector control module per manufacturer procedures.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. The vehicle may experience poor performance, stalling, or failure to start, which could lead to a breakdown or unsafe driving conditions.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for parts and labor, depending on whether the relay, wiring, or control module needs replacement.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.