hey Fred.
8L is usually the ckt to VM. The deadman switch has to engage right away when pedal is depressed a small amount. If it's tow low, like half way down pedal stroke, you get code 8L. The VM wants to see DM switch then travel on the hall effect sensor. If DM switch is intermittantly open, or the small harness directly attached to it, or harness break anywhere between VM and DM switch, it codes out 8L. A weak spring or loose pedal bushings will give 8L too. Give a good tug on the small 2 wire harness at DM switch to check for broken wires.
Always replace the DM switch if in doubt and the spring/bushings as needed.