The ABS light in a Ford Explorer comes on and stays on when there is a problem with the brake system or in cases where spark plugs are wearing thin. This light indicates there is an issue with stopping power that generates issues when trying to stop rapidly or in bad weather. An ABS light sometimes comes on just before engine failure but coincides with all lights turning on.
The antilock brake system or ABS is in charge of ensuring that the brake system does not lock up when trying to stop rapidly or in an emergency situation. In the old days, drivers needed to flutter the brakes or pump them to avoid locking. Modern systems do this automatically when the brake is depressed quickly and completely.
The ABS light in a Ford Explorer comes on and stays on in instances where this systems is not working. This occurs when the system shorts out or stops working altogether. This is an electrical interface and therefore relies on spark plugs and other solutions that generate power and maintain electronic systems. The ABS light indicates the system is offline, the sparks are dying or that the signal responsible for transmitting information between the system and the dash lights is wet.