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IMDSailor · 06-09-2012, 04:30 PM

Went to try and start my coach today only to find I have no 12V chassis power. I'm on shore power right now and have 120V power to the coach. Checked the power level of the chassis batts 13.5ish so that’s good but I can't seem to be able to get the power out of the batts.
I've checked the coach disconnect switch, this could be part of the problem, one of my wheel chalks was against the switch, so the switch looked like it was half on, half off. The coach switch was unaffected. As well as being unable to start the coach, tried using the Battery Boost switch it had no effect. I have no power to the 12V the aux outlets, things like the window fans, headlights etc. don't work either. Just to add a wrinkle, there is power to the dash radio.

Jim_HiTek · 06-09-2012, 04:49 PM

Hmmm.

The half on/half off situation of the switch was probably not good for the solenoid.

Those devices are 'momentary power' to open, again to close. Having continuous power could burn out the coil after a short period. Minutes.

So, I'd recommend you test for proper operation of that solenoid. But only after you have checked all your fuses.

bluepill · 06-09-2012, 05:02 PM

If the chassis battery switch is the style that rotates, try cycling it a dozen times back and forth (on and off) to clean the contacts. If still no power, use a meter or test light to follow the power from the battery and see where you loose it.

IMDSailor · 06-09-2012, 05:06 PM

Thank you for your reply. Where might I find this solenoid? And would a faulty solenoid explain the lack of 12V power to the rest the 12V subsystems.

IMDSailor · 06-09-2012, 05:29 PM

Quote:

Originally Posted by bluepill

If the chassis battery switch is the style that rotates, try cycling it a dozen times back and forth (on and off) to clean the contacts. If still no power, use a meter or test light to follow the power from the battery and see where you loose it.

It's your standard on/off type switch. Normally when I make the switch I hear a click, more like a thunk, when the solenoid engages. I'm not hearing that.

KIX · 06-09-2012, 05:48 PM

Quote:

Originally Posted by IMDSailor

It's your standard on/off type switch. Normally when I make the switch I hear a click, more like a thunk, when the solenoid engages. I'm not hearing that.

Start looking where that "thunk" sound came from. When you find the solenoid you can jump across the two large lugs to verify that you've found the right solenoid. use something like battery jumper cables.

IMDSailor · 06-09-2012, 08:40 PM

Quote:

Originally Posted by KIX

Start looking where that "thunk" sound came from. When you find the solenoid you can jump across the two large lugs to verify that you've found the right solenoid. use something like battery jumper cables.

Thank you for you reply, there in lays the rub, I can't recall where I heard it comming from. Look's like a day of chaseing down wire runs tomorrow.

Hammer Down · 06-09-2012, 09:08 PM

Unplug shore power and see if the generator will start. There might be a rocker switch on the dash left of steering wheel that you might have accidentally bump to the off position. Happen to me once after leaning against dash with my knee getting stuff out of overhead compartment. Good luck.

IMDSailor · 06-09-2012, 09:09 PM

I've located what looks like a solenoid behind the circut board in the Battery Charge Controller fuse box. Could that be the solenoid in question?

IMDSailor · 06-09-2012, 09:11 PM

Quote:

Originally Posted by Hammer Down

Unplug shore power and see if the generator will start. There might be a rocker switch on the dash left of steering wheel that you might have accidentally bump to the off position. Happen to me once after leaning against dash with my knee getting stuff out of overhead compartment. Good luck.

Thank you for your reply. Tried your idea, the generator will start.

Jim_HiTek · 06-10-2012, 12:06 AM

Quote:

Originally Posted by IMDSailor

Thank you for your reply. Where might I find this solenoid? And would a faulty solenoid explain the lack of 12V power to the rest the 12V subsystems.

In older RVs, there is a box named the BCC (battery control center) that is usually very near the batteries. Sometimes in the same compartment. There are 2X solenoids that look like they have a top hat, and another one or two that look like a standard automotive start solenoid in a silver case.

The 2 top hat types are the momentary Off/On devices. If the house solenoid is stuck in Open position, you will not have 12V to the house subsystems, like lights, and if the chassis solenoid is stuck Open, then chassis type devices, like the steps, won't work.

Once you find them, measure the voltage on the large terminals on each side of the solenoid. (You could also remove the small wires and measure the resistance of the coils). Have an assistant operate (press & release) the Main & Aux switches (usually next to the main door of the RV) one at a time while you listen. If you hear a clunk but the voltage doesn't change, there's the culprit. No clunk would mean a bad connection, bad solenoid coil, or bad switch. If you don't have an assistant, you can remove the small wires and using a length of wire, jumper those terminals to battery directly. The wire colors should give you an idea of polarity.

IMDSailor · 06-10-2012, 04:37 AM

Quote:

Originally Posted by Jim_HiTek

In older RVs, there is a box named the BCC (battery control center) that is usually very near the batteries. Sometimes in the same compartment. There are 2X solenoids that look like they have a top hat, and another one or two that look like a standard automotive start solenoid in a silver case.

The 2 top hat types are the momentary Off/On devices. If the house solenoid is stuck in Open position, you will not have 12V to the house subsystems, like lights, and if the chassis solenoid is stuck Open, then chassis type devices, like the steps, won't work.

Once you find them, measure the voltage on the large terminals on each side of the solenoid. (You could also remove the small wires and measure the resistance of the coils). Have an assistant operate (press & release) the Main & Aux switches (usually next to the main door of the RV) one at a time while you listen. If you hear a clunk but the voltage doesn't change, there's the culprit. No clunk would mean a bad connection, bad solenoid coil, or bad switch. If you don't have an assistant, you can remove the small wires and using a length of wire, jumper those terminals to battery directly. The wire colors should give you an idea of polarity.

Hi Jim_HiTek Thanks for the info, great stuff. My coach is a 2011, does your response apply the same?

Sundancer268 · 06-10-2012, 05:49 AM

More than likely you will have a BCC. It might be configured different than the older units, but some method will be required to connect and disconnect the batteries. I would go to the Intellitec WEB site and poke around. I have attached the Intellitec Control Solenoid service manual and I hope that will help. If you do have an Intellitec system, they were very helpful when I had the same problem with the switch being activated all winter when something was thrown in carelessly by myself. Lesson learned. Good Luck, Ed

PS: the two small terminals have NO Polarity. Connecting them one way opens the Solenoid and the other way closes the solenoid. You have to hook a ground wire and a +12 volt wire to make the solenoid work.