P0618 Alternative Fuel Control Module KAM Error

P0618 indicates an alternative fuel control module keep-alive memory error. The module is losing or corrupting stored adaptive or configuration information.

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 alternative fuel components until the module keep-alive power and ground circuits are verified.

Symptoms of P0618

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 P0618

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

Check alternative fuel module power feeds, keep-alive voltage, grounds, battery condition, communication status, freeze-frame data, and related memory codes.
Inspect connectors, fuse feeds, module grounds, water intrusion, voltage drop, recent battery disconnects, programming history, and aftermarket wiring.
Verify stable keep-alive power before replacing or reprogramming the alternative fuel control module.

Related OBD-II codes

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