I did a bit more investigating and I'm still stumped. The chassis batteries are still out of the coach and I put my volt meter across the two battery leads to see if I could detect stray voltage on the chassis main circuit. Only showing 2.5mV.
I also checked the harness under the hood for potential rodent damage from chewed wires and found everything to be ok.
My coach does have an emergency boost switch but its a spring toggle switch that returns to the off position when you release it. It could be possible the relay is stuck though. I need to locate the relay though.
My coach is equipped with a monitor panel with a two way toggle switch and digital readout that shows the status of either the chassis or house batteries depending on which way the switch is depressed. As I expected it reads 14.5V on the house batteries but I was surprised to see 14.4V on the chassis batteries since they are physically not in the coach. This seems to indicate there is power getting to the chassis battery circuit. Another interesting note is that before I replaced the chassis batteries last year (due to age) I had noted that my entry step would not work with dead chassis batteries. With the chassis batteries out of the coach the entry step is operating each time I open the door! This is with the main house disconnect switch off.
My wiper controls are integrated into the Freightliner Chassis Smart Steering wheel. I don't believe there is any way to leave the switch in the on or intermittent position as its push button controlled and re-initializes each time the ignition is cycled.
My chassis batteries are now fully charged and I'm going to try and re-install them and start the coach. I'll also try and locate the emergency boost relay and pull it to troubleshoot.
Thank you all for chiming in on this problem and I'll keep you posted - Paul
