P0626 Fault Code

Generator Field Terminal Circuit High

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0626 fault code indicates that there is a problem with the generator field terminal circuit in the vehicle. This code is usually triggered when the Engine Control Module (ECM) detects a high voltage signal from the generator field circuit, which is outside the normal parameters. The generator is responsible for charging the battery and powering the electrical systems when the engine is running. A fault in this circuit can lead to poor charging performance or complete failure of the charging system.

What are the symptoms of the P0626 code?

Symptoms associated with the P0626 code may include:

• Battery warning light illuminating on the dashboard.
• Dimming or flickering lights.
• Electrical accessories not functioning correctly or having reduced performance.
• Difficulty starting the vehicle due to insufficient battery charge.
• Fluctuating voltage readings when testing with a multimeter.

What causes the P0626 code?

Common causes for the P0626 code include:

• Damaged wiring or connector issues in the generator field circuit.
• Failed voltage regulator in the generator.
• Short circuits causing excessive voltage readings.
• Poor ground connections affecting the field terminal.
• Faulty generator itself that has internal issues.

How to fix P0626?

To resolve the P0626 fault code, follow these steps:

1. Inspect the wiring and connectors associated with the generator field circuit for any signs of damage or corrosion.
2. Test the generator to ensure it is functioning correctly and producing the necessary voltage.
3. Check the voltage regulator for proper function; replace it if necessary.
4. Ensure all ground connections are clean and secure.
5. If the issue persists, consider replacing the generator if it is faulty.