ABS light.

Doesn't it require plugging a code reader into the Allison diagnostic port?

wheel sensor has excessive gap to the tone ring is one of the causes. You can try driving 15 mph and hit the brakes three time. If not do 30 mph and the same on the brakes. This comes from a friend who has your chassis.

The system has an active fault. Scan the vehicle. Find the fault. Correct it. Clear codes. Lights out.

sch911 wrote:
Scan the vehicle. .

with what?

on most automotive vehicle abs lights reset on their own when you turn the key the abs module reads resistance on all sensors and soliniods if it finds one it doesnt like the light stays on if the problem is corrected when you drive down the road light will go off look at all the wheel speed sensors and see if you have a broken wire

Are you in Oak Haebor? Call Powers up on Ault Field Road. They might be able to help/
OP has diesel with Cummins on Spartan chassis.

enblethen wrote:
Are you in Oak Haebor? Call Powers up on Ault Field Road. They might be able to help/
OP has diesel with Cummins on Spartan chassis.

I don't know. "" Powers "" nothing in phone for them .

Telephone number (360) 720-2233
My memory, which is getting bad, remembers they are just east of the entrance to navy base. Been a while!

enblethen wrote:
Telephone number (360) 720-2233
My memory, which is getting bad, remembers they are just east of the entrance to navy base. Been a while!

Now it is Barber shop.

Have you tried calling Eric's over in Squim?
Eric's