The P2148: Fuel Injector Group ‘A’ Supply Voltage Circuit High indicates that the voltage in the fuel injector group ‘A’ supply circuit is higher than expected. This can be caused by a faulty fuel injector, wiring problems, or issues with the power supply, which can affect the performance of the fuel injectors and engine operation.
P2148 – Quick Overview
Code | Information |
---|---|
Meaning | P2148: Fuel Injector Group ‘A’ Supply Voltage Circuit High |
Is it serious? | Yes, it can lead to incorrect fuel injection, causing engine performance issues such as misfires or high fuel consumption. |
Possible causes | – High voltage in the fuel injector group ‘A’ supply circuit – Faulty fuel injector group ‘A’ – Wiring issues or power supply problems |
How to diagnose? | – Measure voltage in the fuel injector group ‘A’ supply circuit – Test the fuel injector group ‘A’ – Inspect wiring and connections |
P2148 Meaning
The P2148 code indicates that the voltage supplied to fuel injector group ‘A’ is higher than specified, which can cause incorrect fuel delivery, leading to engine misfires, poor fuel economy, or other performance issues. This fault could be due to a malfunctioning injector, wiring faults, or problems with the power supply to the injectors.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for any additional related codes that may give more context on the issue within the fuel system or power supply. | OBD-II Scanner |
Measure Voltage in the Supply Circuit | Use a multimeter to measure the voltage at the fuel injectors in group ‘A’. Compare the readings with the manufacturer’s specifications to determine if the voltage is too high. | Multimeter |
Test the Fuel Injectors | Use a diagnostic tool to test the functionality of the fuel injectors in group ‘A’. Replace any faulty injectors if they are not performing as expected. | Diagnostic Tool, Multimeter |
Inspect Wiring and Connectors | Visually inspect the wiring and connectors for fuel injector group ‘A’ for signs of damage, loose connections, or corrosion. Repair or replace as needed. | Flashlight, Multimeter |
Inspect Power Supply Components | Check the power supply components, including the fuse, relay, and ECU, to ensure that they are providing the correct voltage to the injectors and are not causing an overvoltage situation. | Multimeter, Wiring Diagram |
Check for Shorts or Electrical Faults | Perform continuity tests on the wiring to detect any shorts or other electrical faults that may cause high voltage in the supply circuit. | Multimeter, Wiring Diagram |
Clear the Code and Test Drive | After repairs or adjustments, clear the code using an OBD-II scanner and take the vehicle for a test drive to ensure that the issue has been resolved. | OBD-II Scanner |
Recheck for Codes | After the test drive, re-scan the vehicle to ensure the P2148 code has not returned. | OBD-II Scanner |

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Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)