1F4A10

What the Code Means

Code 1F4A10 indicates that the engine control unit (DME) cut power to the injectors and ignition coils after detecting a short to ground. This is a protective measure that prevents electronics damage or fire. The fault often comes with other electrical issues.

The injector and ignition coil power supply circuit includes the DME, relays, fuses, and wiring harnesses. On a short to ground, the DME cuts power to protect the components.

Symptoms

• Engine won't start
• No ignition spark
• No fuel injection
• Multiple warning lights on the instrument cluster

Diagnosis and Repair

Step 1: Diagnose with ISTA

Connect the ISTA diagnostic scanner to read codes and analyze live data.

Step 2: Check for a Short to Ground

Use a multimeter to check the ignition coils and injectors for a short to ground. Inspect the wiring harnesses for damage.

Step 3: Check the Power Distribution Module and Relays

Check the relays and fuses that supply power to the injectors and coils. Replace them if needed.

Step 4: Replace Faulty Components

Replace the faulty ignition coils (part number: 12138616153) or injectors.

Step 5: Check the DME

If the short to ground damaged the DME, the control unit will need repair or replacement.

Secondary Damage

Ignoring the fault can take out the DME, which means a costly ECU replacement. A short to ground can also damage the power distribution module. Do the repair right away.