USE/STORE Swtich

[joekarla05]

2017 Thor Hurricane 34J is my model.

Today I went out to the Motorhome to exercise the engine and start the generator to let it run for 30 minutes. The Use/Store Switch acted funny and didn't switch to the use mode when I hit it, then after a short bit, it kicked on and was ok. Then, as I was shutting down the generator and such, I switched it to Store mode, forgot about something, and switched it back to use, and heard it click, but the lights would not kick on. So I cycled the switch again, and if I hold the switch to "use" the lights work, etc. But when I let go it shuts off... any ideas?
It had been 2 weeks since I last went to the storage shed to check on it, but have not had an issue before... could the cold have impacted the switch "latching"? or Am I dreaming on that, there had not been any issues before.

 

[DavidEM]

The use/store switch is based on a remote solenoid that is activated by the switch. It is a latching solenoid which only needs to be activated for a second or so to switch.

It sounds like the latching is failing and you need to replace the solenoid. Very common problem.

Sorry, I can’t help you with the part, but someone will chime in with a recommendation.

David

 

[16ACE27]

Let's get the generator running out of the way first: Onan recommends running the generator at least once a month at, at least half load for 2 hours to properly exercise it. It's right in the maintenance section of the Onan Users Manual.

Now for the USE/STORE switch/latching relay:
The switch is a Dual Pole Dual Thow sprint return to center momentary switch. Pushing USE shifts the latching relay to close the disconnect contacts; pushing STORE shifts the latching relay to open the disconnect contacts.

Since it won't stay in the closed position unless applying the electro-magnetic shifting field, I suspect the latching relay itself has issues and needs to be replaced. I don't think you could see the same symptom unless someone had messed with the switch wiring.

 

[VetPartTimer]

Or, your batteries are weak/not holding enough voltage. This happened to me.

New batteries, problem solved.

 

[joekarla05]

Or, your batteries are weak/not holding enough voltage. This happened to me.

New batteries, problem solved.

All batteries are brand new. I’ve been going out weekly to start and charge them etc and had no issues until today.

 

[joekarla05]

Let's get the generator running out of the way first: Onan recommends running the generator at least once a month at, at least half load for 2 hours to properly exercise it. It's right in the maintenance section of the Onan Users Manual.

Now for the USE/STORE switch/latching relay:
The switch is a Dual Pole Dual Thow sprint return to center momentary switch. Pushing USE shifts the latching relay to close the disconnect contacts; pushing STORE shifts the latching relay to open the disconnect contacts.

Since it won't stay in the closed position unless applying the electro-magnetic shifting field, I suspect the latching relay itself has issues and needs to be replaced. I don't think you could see the same symptom unless someone had messed with the switch wiring.

Any idea where that relay would be located ? The wiring has not been messed with in any manner.

 

[16ACE27]

Well since it still "clunks", follow the clunk. Most likely behind the Power Center. It may look like:

or like this:

 

[ghnl]

All batteries are brand new.

No guarantee they are good. I've had a "brand new" battery fail.

A simple voltage test is a good start on checking their health. With everything off and not having been on the charger for a few hours a good battery should read 12.6V. 12.0V is almost dead. The betterer test is a load test. But that takes more than a simple voltmeter.

 

[VetPartTimer]

No guarantee they are good. I've had a "brand new" battery fail.

A simple voltage test is a good start on checking their health. With everything off and not having been on the charger for a few hours a good battery should read 12.6V. 12.0V is almost dead. The betterer test is a load test. But that takes more than a simple voltmeter.

Yes, this.

Mine were only 6 mos old.

 

[joekarla05]

Or, your batteries are weak/not holding enough voltage. This happened to me.

New batteries, problem solved.

This same switch situation happened to you? where it would work if held in the "use" position?

 

[16ACE27]

This same switch situation happened to you? where it would work if held in the "use" position?

Very low batteries MAY cause this symptom, BUT, if they were that low they would not be able to start the generator.

 

[joekarla05]

Very low batteries MAY cause this symptom, BUT, if they were that low they would not be able to start the generator.

That was my thought. I have seen it in some other forums, but the batteries are sitting idle at 12.6 so I am fairly sure it's the switch/ relay that you referenced. Time will tell.

 

[DavidEM]

Your symptoms describe exactly what I would expect with a bad latching solenoid. Replace the solenoid and all should work fine.

David

 

[joekarla05]

Your symptoms describe exactly what I would expect with a bad latching solenoid. Replace the solenoid and all should work fine.

David

Thank you, I will be investigating that this weekend hopefully.

 

[joekarla05]

Solenoid replaced, seems to have fixed issue, but the new solenoid seems to have the polarity reversed for what turns thebswitch on and off... going to continue investigating and running some tests, but it seems to be functioning as it is supposed to at this stage.

 

[PS89]

BTW, which solenoid was used in your MH? One of the ones that Ace posted photos of or something else?

 

[joekarla05]

 

[joekarla05]

This is the old one the new one has a fuse at the top vs just the inline

 

[joekarla05]

Very low batteries MAY cause this symptom, BUT, if they were that low they would not be able to start the generator.

So I switched out the Solenoid and wired it the same way that the previous one was... but the polarity seems to be reversed...use is store and store is use... i didnt touch anything else except when I disconnected the negative terminals in the battery compartment.... any ideas? Ever seen something like this before? Any help is greatly appreciated.

 

[16ACE27]

So I switched out the Solenoid and wired it the same way that the previous one was... but the polarity seems to be reversed...use is store and store is use... i didnt touch anything else except when I disconnected the negative terminals in the battery compartment.... any ideas? Ever seen something like this before? Any help is greatly appreciated.

Swap the wires on the two control (small) terminals.