2007 IC CE200 and 2011 IC300 both with MaxForce 7 engines. The ABS,TC, and brake pressure lights will come on itermitently.We shut the engine off and restart and they go off but some times come back on while driving. Noticed on the start first thing in the morning it takes a while for the dash warning lights to all go off. The ABS,CT, and the brake pressure are the last ones to go off and you can't release the parking brake until they go off it may take a couple of minutes or even more for them to go off. Thanks for any help.
I agree with the pump system going bad. At the dealership it was common for this to happen and the entire pump assy. get replaced. I am not sure if it is possible to replace individual components of the pump.
something I forgot was to mention was the long initial build up time may also be caused by the breather cap being plugged, but that should not affect it going down the road...
Another item to check is the four mounting studs that attach the unit to the frame are the ground circuit for the motors/ecm. I've had to remove them clean the frame, add copper/conductive antisieze and reinstall. This generally helps along with taking the Kevlar wrap off of the wire loom to inspect for abraded or corroded wires/ connections. Replace with split loom.
The lengthy charge time at initial start up would make me think the pumps are getting weak.
If you do decide to change the pumps (very easy but messy) have the new ones in hand so as to install them asap after the old ones are out. I would even change one then top the reservoir off then change the other. Reason for this is bleeding or making the pumps prime after a total fluid loss is a pain in the butt. I didn't have the pressure bleeder the manual said you need but a spare cap and a air pressure regulator got the job done.