FMI 839 CAT Fault Code

Cause :

The job of the Starter Relay Circuit is to provide a power source to the starter to crank and start the engine. Depending on the specific vehicle and its drivetrain configuration, there can be multiple components involved in this process.this process determines the absence of a power source or ground, then perform a continuity test to check the integrity of the wiring, ignition switch, and other components. Continuity test must be performed with the power removed from the circuit while reading for wiring.