Hello,
Yes, it is possible the transfer switch has gone bad.
You say you have tried the breaker, so I assume you mean the breakers both at the genset and in the coach. Does everything work correctly when on shore power?
To test the transfer switch, remove the cover from the switch. There will be 3 main lines going in to it - shore cord, genset, and the feed to the the breaker box.
BE VERY CAREFUL WHEN DOING THIS TEST, AS YOU WILL BE WORKING WITH LIVE ELECTRICITY.
Set your meter to VAC. The switch should have a schematic inside the cover that identifies which wires are the genset. Start the genset, wait one minute for the timer to activate, and probe the black to white wires of the genset connection. If there is voltage, probe the black to white breaker box connections. If there is no voltage, the transfer switch is bad. If there is voltage, the problem is somewhere else.
The switch will generally be in one of two places.
The first is inside the compartment where you store your shore cord. Remember, the shore cord and genset go to the switch. Follow the shore cord first.
The second most common place attahced directly to or behind the power distribution center in your coach. Find the main breaker box. Sometimes you have to remove the power distribution center, and sometimes you can access the switch by removing a panel around ro beside it.
Technician
Certified on Onan and Generac generators
No problem.
I wish I could have been more specific than that, but with the mulitude of mounting locations and the many different types of transfer switches available, I would have to see the unit to be exact.
voltage meter only shows 1.0 when you check the generator side of the switch. Nothing on the output side. checked right at the generator using the stud on the bottom and it read 24.
Houston, we have a problem.
But we are good, and we can take care of it. Right?
What is the full model number of your genset? There were 2 styles of Marquis, and they have nothing in common.
we sure can try. i'll get the numbers and be right back
OK,
I would like for you to check the following:
Find the voltage regulator connector inside the control box. It is a white 12-pin connector. Unplug the connector. Set your meter to ohms. Testing on the harness side of the plug, not the voltage regulator itself, ohm across pins J4-9 and J4-10. It should read 20-30 ohms.
If it reads 50 ohms or higher, we need to check the brushes and slip rings. Remove the air cleaner. Directly behind the air cleaner is the end bell of the generator. In the middle of the end bell is a small plastic rectangular cover. Use a flat tip screwdriver to pry the cover out and expose the brush block.
The brush block will have 2 round holes in it with a single uninsulated wire going through. This is the brush lead. Use a small probe or piece of small diameter stiff wire and push the probe through the hole until it touches the brush. Mark the probe where it is flush with the brush block. Remove the probe and measure from the mark to the end of the wire. If it is more than 1", the brushes are worn out and must be replaced. Remove the 2 screws securing the brush block, turning each screw 3-4 times each. The brush block must come out straight, as it is made of ceramic and is very fragile. Be careful not to drop the screws down into the end bell. They are very difficult to retrieve. Use the wires to help pull the brush block out. Inspect the ends of the brushes. They should be smooth and not cracked or chipped. They should be worn into an even arch pattern. They should slide freely into and out of the brush block. If they stick or bind, clean the brush block with electrical contact cleaner. Inspect the slip rings. They are the 2 bands that the brushes ride on. They are made of copper and should be as shiny as a new penny. They should be smooth and have no pits or scratches. If they are dirty, you can clean them by removing the spark plug wires and grounding them out. Attach a piece of scotch brite to the end of a small stick. Press the scotch brite against the rings and crank the set. Do not crank for more than 15 seconds without stopping for a minute or two to let the starter cool. When the rings are clean, ohm across them. They should read 20-30 ohms. If not, the rotor is bad and must be replaced. If it is good, reinstall the brush block.
Reconnect the 12-pin connector at the voltage regulator. Set your meter to VDC and connect the black probe to a good ground. Insert the red probe into the back of the plug at wire J4-7 and press the start button. It should read at least 10V. Insert the red probe into the back of the plug at wire J4-9 and press start. It should read at least 12V and climb as you hold start. Insert the red probe into the plug at wire J4-10 and press start. This voltage can vary from 1.5 - 20 volts, as long as there is voltage showing.
What are the results of these tests?
I'm sorry to hear that you are almost as busy as me (I work 3 jobs and am in the middle of putting a new engine in my wife's truck). Wish we could have gotten it going to help save you some money.
Any time you need help, just ask and we will Just Answer!
Only 3 things come to mind - a loose connection that got jarred, a voltage regulator that is getting ready to go, or a dirty brush that made better contact with the slip ring.
I would highly encourage you to do the voltage regulator and slip ring test that I gave you when you get a chance.