ONAN wire not attached to anything

[Schultzes]

Hello, this is my first post in the forums.

I have 1999 Damon Ultrasport with propane ONAN 6300 GenSet. My Onan generator has a wire that goes behind the oil dipstick and continues under it to the back. I do not know what part it is going to on the backside of the generator, and the backside is covered so I cannot see anything when underneath and behind. Inside the panel I do not find a loose wire or terminal for it to connect to. The wire has a male spade on it, everything in the panel that is open for a connection requires a female connector. Looking at photos online it appears the wire should be inside the panel.

The generator will run when started at the generator, and provide power. The remote start is not currently working, but I can shut it off remote.

Any ideas on where this wire is coming from on the backside of the generator or what it connects to? I have the manual, but it does not have any drawings or diagrams that help me out with reference to where the wire is attached to and coming from, but if someone knows that I can probably then start relating to an electrical schematic in the manual.

[campcop]

Is this wire hot? If you press the remote start is this wire hot or go to ground?

What year and make MH? Different manufacturers use different colored wires.

Edited August 30, 2020 by campcop

[kaypsmith]

1 hour ago, campcop said:

Is this wire hot? If you press the remote start is this wire hot or go to ground?

In most likely to be a ground otherwise it would blow a fuse in the event that it shorts to ground. But as CC said not all coach manufacturers wire things alike. Use a VOM (volt ohm meter) to check to see if it does become hot  when trying to crank with the remote start. Have someone push the button while checking with the meter for 12 volts, if no power then, try holding it to ground to see if it does start the generator. Be sure to check for voltage first before grounding. Since it is a generator, there is a possibility that it is an AC neutral.

[Schultzes]

Thank you for the responses.

The MH is a 1999 Damon Ultrasport.

We tested the wire holding the switch and no readings on the meter, tested it to ground and nothing. Started the generator locally and tested the wire for voltage, nothing. Turned off the generator and attempted to ground it and start remote also.

Got into the dash and had a look at the remote switch and do not see any wires free, also took a look at where that harness attaches to another outside the generator controller and did not see anything apparent. I'll be doing some more poking around to verify the contacts are good at the switch and then the harness.

Not sure that the wire I am seeing hang free goes to remote starting or to another component within the generator side of the unit.

Edited August 30, 2020 by Schultzes

[campcop]

That wire looks pretty clean. Did you just notice this? I found this.   https://onan.xmsi.net/940-0125 Onan 6.3KW NHL (spec P) RV Genset Operator's manual (01-1983).pdf

 

it looks like that wire does not go to remote start.

Edited August 30, 2020 by campcop

[dickandlois]

4 hours ago, Schultzes said:

Thank you for the responses.

The MH is a 1999 Damon Ultrasport.

We tested the wire holding the switch and no readings on the meter, tested it to ground and nothing. Started the generator locally and tested the wire for voltage, nothing. Turned off the generator and attempted to ground it and start remote also.

Got into the dash and had a look at the remote switch and do not see any wires free, also took a look at where that harness attaches to another outside the generator controller and did not see anything apparent. I'll be doing some more poking around to verify the contacts are good at the switch and then the harness.

Not sure that the wire I am seeing hang free goes to remote starting or to another component within the generator side of the unit.

Look at the post with the Manual link !

Think the wire you found goes to the circuit pictured on the last page . The wire looks like it might be a faded yellow wire, related to the remote starting switch. wire number 3 in the drawing.

Rich.

[Schultzes]

Figured out the wire goes to the oil pressure switch. Interesting that the generator runs and carries load without issue with this disconnected. As an additional note, I have only owned the RV for a year and not worked on the generator. Now that I know what the wire is to I will figure out where it attaches and see if it has a bypass loop of some sort within the box allowing it to run.

Looks like the remote start is a different issue to track down.

Thanks for the help.

Edited August 31, 2020 by Schultzes

[rls7201]

Remove your oil filter and you should be able to see the oil pressure switch.

The oil pressure switch is normally closed and goes open circuit with oil pressure. Thus the engine runs with the wire disconnected.

Richard

Edited September 1, 2020 by RLS7201

[hermanmullins]

Before removing the oil filter why not get a new filter, fuel filter and air cleaner and do a complete service at the same time.

Herman

[Schultzes]

23 hours ago, RLS7201 said:

Remove your oil filter and you should be able to see the oil pressure switch.

The oil pressure switch is normally closed and goes open circuit with oil pressure. Thus the engine runs with the wire disconnected.

Richard

Thank you, that assists in understanding why it will run with it not attached to anything.

[Schultzes]

Ok, I’m not figuring out where the wire coming from the oil pressure switch is supposed to attach. The wire is attached to the oil pressure switch on one end but where it goes escapes me. I’ve looked at the electrical diagrams in the manual but that is not helping me. Anyone know where this should be attached?

[rls7201]

LOP SW (low oil pressure switch) in upper right hand corner of schematic.
NC=normally closed.
Connection point 12

 

 

Richard

Edited September 5, 2020 by RLS7201