FMI 824 CAT Fault Code

Cause :

When the ignition switch is turned to ON, voltage from the ECM's MREL terminal is applied to the EFI MAIN relay. This causes the contacts of the EFI MAIN relay to close, which supplies power to terminal +B of the TCM.If the charge system light stays on, or comes on while driving, there may be a problem with the electrical charging system. Driving while this light is on could drain the battery.