P2156 Fault Code

Fuel Injector Group D Supply Voltage Circuit Low

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

The Fuel Injector Group D Supply Voltage Circuit Low fault code indicates that the voltage supplied to the fuel injectors in Group D is lower than expected. This condition can prevent the injectors from functioning properly, leading to poor engine performance and inefficient fuel usage.

What are the symptoms of the P2156 code?

Common symptoms associated with this fault code include:

• Reduced engine performance
• Hesitation or stalling during acceleration
• Rough idling or engine misfires
• Difficulty starting the vehicle
• An illuminated check engine light on the dashboard.

What causes the P2156 code?

Several factors can contribute to this fault code:

• A weak or failing battery that cannot supply adequate voltage
• Poor electrical connections or corroded wiring in the fuel injector circuit
• A malfunctioning fuel injector relay
• An issue with the Engine Control Module (ECM) not providing the correct voltage
• Short circuits or grounding issues in the wiring harness.

How to fix P2156?

To resolve the Fuel Injector Group D Supply Voltage Circuit Low issue, follow these steps:

1. Check the battery voltage and condition to ensure it is operating correctly.
2. Inspect the fuel injector wiring harness for damage or corrosion.
3. Test the fuel injector relay and replace it if necessary.
4. Use a multimeter to measure the voltage at the injectors and ensure it matches specifications.
5. Check the ECM for any fault codes and perform a reprogramming if needed.
6. Clear the fault codes and take the vehicle for a test drive to confirm the issue is resolved.