P0619 Alternative Fuel Control Module RAM/ROM Error

P0619 points to an alternative fuel control module RAM or ROM error. The module has detected an internal memory or program integrity problem.

Code details

Generic OBD-II · P0

System: Computer
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not replace fuel injectors, regulators, or sensors for P0619 before verifying the control module and its power supply.

Symptoms of P0619

Check-engine light, sometimes with several unrelated codes at once.
Warning lights, a no-start, or intermittent electrical faults.
Communication or module-reset problems on a scan tool.

Common causes of P0619

Low battery voltage, poor grounds, corroded connectors, or blown fuses.
Wiring or network (CAN bus) faults between modules.
A module software/programming issue, or rarely a failed controller.

Useful checks before replacing parts

Review module power feeds, grounds, battery voltage stability, communication faults, freeze-frame data, and whether the memory error returns immediately.
Inspect module connectors for corrosion or water intrusion, harness damage, voltage spikes, programming history, and related alternative fuel system codes.
Confirm software level, power integrity, and network health before replacing the alternative fuel control module.

Related OBD-II codes

These nearby computer entries can help compare wording and pin down the fault area.