No 12 VDC Power - 2005 Monaco Diplomat

[Geffery]

I have an electrical problem all was ok when i parked and plugged into 50 Amp power cord for a few weeks. Sides would go out could adjust thermostat heat, refrigerator was working, ceiling lights and wall lights worked, could start generator, dash radio would turn on, step lights would work. Now none of them work. Checked 12v switch at door step no change.

[Jdw12345]

Salesman Switch bad?

 Or solenoid?

Edited March 15, 2023 by Jdw12345

[Dr4Film]

Sounds like you have lost your 12 VDC power. Bypass the Battery Cutoff solenoid and all your 12 VDC power should be good after that.

[MyronTruex]

It is always a good start right at the battery banks to check their voltage.

If both banks are charged, you can move to the infamous salesman switch/solenoid as suggested. 

[Geffery]

On 3/14/2023 at 9:25 PM, Dr4Film said:

Sounds like you have lost your 12 VDC power. Bypass the Battery Cutoff solenoid and all your 12 VDC power should be good after that.

Thank you for your response i will try that 

Thanks i will try bypassing salesman solenoid 

[96 EVO]

8 minutes ago, Geffery said:

Thank you for your response i will try that 

Thanks i will try bypassing salesman solenoid 

Or, have your wife press the salesman switch while you have your hand on the side of the solenoid. Should feel it clunk into position.

[Tom Cherry]

2 hours ago, 96 EVO said:

Or, have your wife press the salesman switch while you have your hand on the side of the solenoid. Should feel it clunk into position.

If the generator will not start, then odds are the house bank is dead or low.  In most Monaco’s the boost switch is powered from the house bank. Therefore with no house power, no boost circuit

My suggestion would be to start the engine and then use a single automotive jumper cable and charge the house. 
 

What I don’t understand is if the rig is still plugged in?  If so, then there is a charging issue.  As Myron said, you need to isolate and understand the issue.  If the rig is plugged in to 50 A, then the inverter should be charging

The generator not starting is NOT controlled by the salesman switch

if the inverter is not working, then running the Generator will not recharge the house bank

The single jumper cable between the positive of the house and chassis and letting the engine run will recharge the house.  Should take maybe 2 hours at idle to charge.  Turn on the cruise control and push the resume switch.  That should give you fast idle

But, the inverter not charging has to be addressed.  One thought is that the inverter went into low battery (voltage) cut off and shut down

Look at the control panel and your inverter manual and make sure the inverter, if on shore or Genny, is charging after you let the engine run for half an hour or so  if it is charging now, then disconnect the jumper and let the inverter work. In 3 hours, the batteries should be charged. If the batteries were low, then house power should come back. If not then look at salesman solenoid. Bypassing it with dead house batteries ain’t gonna fix it