P2148
OBD-II Diagnostic Code
Severity: CriticalWhat it means
P2148 means the power supply circuit to a group of fuel injectors has an open circuit or low voltage.
The affected injectors cannot fire, causing misfires and rough running.
Check the injector fuse, wiring harness, and power relay.
Affected Models
- All OBD-II vehicles (1996+)
- Common on diesel engines
Common Causes
- Injector power supply fuse blown
- Wiring harness damage to injector group
- Injector relay failed
- ECM injector driver fault
- Corroded injector connectors
How to Fix It
-
Check the fuel injector fuse.
A blown injector fuse cuts power to the entire injector group.
Replace with the correct amperage fuse. -
Inspect the injector wiring harness.
Look for damaged or melted wires near the injectors.
Heat from the engine can damage the harness over time. -
Test the injector power relay.
The relay provides 12V to the injectors.
Swap it with an identical relay from another circuit to test.
Frequently Asked Questions
Will the engine run with P2148?
It may run poorly or not at all, depending on how many injectors are affected.
If an entire bank of injectors loses power, that bank will not fire.
What is an injector group?
Engines group injectors into banks or groups that share a common power supply.
Group A is typically one bank of a V-engine or the first half of an inline engine.