Dead dashboard, coach doesn't respond to key

[pbustamante41]

Coach dash is dead. I am plugged in and the everything on the Coach side is working however the chassis side is dead. I noticed the air leveling system panel was flashing red this morning and when checking it out found that it's not responding and when I turned the key on nothing happens. Everything was functioning on the leveling system last night. I haven't had any issues with anything. I turned off and on the salesman switch with  no luck. Where should I check 1st. 

[BradHend]

Start with the battery bay chassis switch. Ensure it is working. 

And obviously check your batteries aren’t dead. 

And battery connections are good. 

[knightmovesrv]

jiggle the key switch, they use old GM ignition switch and can lose contact or even come apart. Bayyery switch is first check for sure

[Frank McElroy]

As others have said, the first thing to check is the chassis battery voltage.  If you find the chassis batteries are dead, check the voltage across Big Boy to be sure both large battery connections are reading the same voltage.  Being plugged in, the inverter will charge the house batteries and Big Boy will connect the chassis batteries so they also will be charged.

[Dr4Film]

Sounds like the 12 VDC power is not getting to the Front Run Bay electrical panel.

Have you checked in there to see if all of the telltale lights are lit up correctly?

Previous advice is also important. Power has to come from the Rear Run Bay to the FRB.

[Tom Cherry]

My Shade Tree reaction is.  Use a Single Jumper Cable and jumper the House and the Chassis.  If that fixes it....you have dead Chassis Batteries.  That Jumper Cable will allow them to charge.  As Frank pointed out, the Big Boy, via the controller for it, is supposed to keep both banks charged.  The Big Boy has been known to have pitted contacts.  For an emergency fix....use the Jumper Cable hookup.  

It will take a while to recharge the Chassis from the inverter (plugged into 50 A power or running the Generator).  If your dash comes to life....then driving it will really pump amps into it and recharge the Chassis.  It does NOT hurt to drive with the batteries connected via a Jumper.  The Big Boy is nothing by a large solenoid with contacts capable of carrying up to 200 A.

Then you can diagnose.  Here is a file on HOW to take apart and clean the big Boy.  

If I recall correctly, it is almost impossible to use a volt meter probe and check the control voltage (small contacts) on the Big Boy the way it is mounted.  I had an issue with my Big Boy once when we lost power at storage.  I ended up just popping in a new one and plan to refurbish mine and carry it....

Once the Chassis is recharged, you test for voltage across the Big Boy's high current studs.  You can, as Frank said, do that now.  One side should have POWER (to Ground) and the other side, if the Chassis is dead....NO VOLTAGE.  That is a quick test.

THEN pop on the Jumper and get the Chassis to have a quick (30 - 45 min) surface charge. You should be able to start the engine easily, even with the Jumper.

Good Luck...

[mrbill1951]

Had a similar issue two years ago.  Mine would also stop while driving and everything shut off.  That was exciting.  I replaced the ignition switch, ignition solenoid and fuses. Don't know for sure what the issue was, but one of these items fixed it and they were cheap.  I strongly suspect it was the ignition switch and it was pretty simply to swap out.

[Ivylog]

Turn on the headlights to test for dead engine batteries.