Last night the lights in the Barth went out. Actually everything that operates on 12VDC stopped operating. Now realize as you get to know your coach better, almost everything requires 12VDC to operate. The LP gas will not turn on unless the "sniffer" opens the valve. The refrigerator will not operate on 120AC or LP because the control board is 12VDC.

Last night I checked the batteries and they were good, 13.56V. I checked Intelli-power 9100 and it had good output, 13.76V. About all I could check last night.

While Pondering the problem last night and this morning, I figured this had to be a problem that had to be very early in the DC system. Before any breakers, fuses, etc. This problem was just like someone had turned this switch off.

If I can find the relay that this switch controls, I might be on to something. Not under the bed where the Intelli-power, breaker panel, Auto AC power switch, etc is located. Not in the electrical compartment at the front of the coach. There that sucker is. Right in the middle bottom part of this picture of one of the walls on the right side of the rear engine compartment.

And guess what? It tested bad. 13.76V on one side and nothing on the other. Double checked that it was getting power to the activation terminal and it was okay. So I pulled it out.

Off to my nearest NAPA store. Needed One 12V constant-duty solenoid.

Back home, quick installation:
And presto, just like magic, we have lights. And hot water. And cold beverages.

On a side note about inflation. The solenoid I removed still had a price sticker on the back of it. $17.95 Have no idea when it was purchased. On September 22, 2011, the one from NAPA was $68.00

Nick

Kewl!

Nice write up. I like all the details.

I have been noticing that this solenoid, located just forward of the engine in our Breakaway, seems to run warm-- is this common or how "things" are supposed to be?
Given the warmth it generates, I suspect it uses a fair amount of battery capacity.
Bud

Bud, the bad solenoid was also warm to the touch. It was marked 12V-35. There was no "A" to indicate Amps but I think it was probably rated at 35 Amps. The solenoid I bought was a heavy duty unit rated at 80 Amps. I don't think the purpose of the solenoid is circuit protection. It is to complete a circuit. Fuses and circuit breakers serve that purpose, so I didn't have any concerns about installing a solenoid rated that high. Hopefully, It will serve it's designated purpose for a long time.

Nick

There's warm and then there's "warm". The relay, having a coil, will run warm, but it should draw less than 1 amp. You should be able to touch the relay without having to retreat due to heat. Most folks can tolerate 120°, which isn't overly hot.

Best would be an IR thermometer to get an accurate reading; periodic readings would confirm integrity or deterioration. Windings on a solenoid coil are typically insulated with varnish. When this starts to break down, heat increases, leading to accelerated breakdown.

Bottom line: It's much more convenient to replace in your driveway than in the boonies.

When Gary visited us here in St. Charles guess what we tried to find unsuccessfully since NAPA was closed in the evening. Next morning Gary got one from NAPA and we (Gary and the onlooker) installed it. Looks like, don't leave home without it.

Nick & Rusty
Thanks for the info-- I had noticed the warmth-- so far not hot-- and wondered how normal this was. As we have been thinking we don't get a lot of boondocking time before voltage drops, this could be the source of power consumption. A new solenoid might reduce this. Does this solenoid need to be a constant draw type because the switch is only an on/off type ?

Bud

we had a similar problem a couple month ago but on our Regal it was the black oval/round 80amp relay (seen on your picture just to the left of the part you replaced), the battery would not charge. We got a replacement at a electrical store in Nashville for $58 plus $550 for repair of the fuel relay on our Volvo car that quit on a 105F day and $100 for a rental car to get us home, plus another trip to Nashville to pickup the Volvo. Note to all Volvo owners, this fuel relais will quit due to bad soldering.

Remember that a solenoid is really just a remote switch which ultimately connects 2 wires. If this happened to me in the middle of the the night, I would a) jumper around the solenoid or b) remove the wires and connect them together to get through the night.

The trick of course is to know where to look for the solenoid, another argument for the owner to be well acquainted with all systems aboard. Years ago a friend worked for the phone company. All their systems then were rotary dial mechanical relays and lots of them. When he retired they put him on call and when they had serious voodoo in the system he would come in, like when many of Detroit's lines were inoperable due to transfer station relay problems. He would go in, study the failure, go to a specific location, bang on the relays, restore the system and bill them 1001 dollars. When someone complained that seemed a lot for a tap of the hammer, he replied "the 1 dollar is for the labor, the 1000 is for knowing where to tap!"

Good idea to upgrade to higher amps on almost any switch device when replacing.. cheap insurance and usually means no repeat problems. Go with continuous duty relays, the coils on the intermittent duty ones will probably overheat in steady service.

quote:

Originally posted by bud@YXY:
Nick & Rusty
Thanks for the info-- I had noticed the warmth-- so far not hot-- and wondered how normal this was. As we have been thinking we don't get a lot of boondocking time before voltage drops, this could be the source of power consumption. A new solenoid might reduce this. Does this solenoid need to be a constant draw type because the switch is only an on/off type ?

Bud

The relay - as has been noted above - needs to be "constant-duty", as the intermittent types can't handle being energized for any length of time. The wall switch turned powers the coil (closes the relay) all the time until turned off.

quote:

Originally posted by Marvin+Doris:
we had a similar problem a couple month ago but on our Regal it was the black oval/round 80amp relay (seen on your picture just to the left of the part you replaced), the battery would not charge. We got a replacement at a electrical store in Nashville for $58 plus $550 for repair of the fuel relay on our Volvo car that quit on a 105F day and $100 for a rental car to get us home, plus another trip to Nashville to pickup the Volvo. Note to all Volvo owners, this fuel relais will quit due to bad soldering.

That round device is either a fusible link or more likely, a circuit breaker; it's not wired like a relay. The red button could be a reset. An internally-shorted relay coil can produce enough heat (from excess current) to melt solder.

Marvin and Doris, the fuel pump relays on the older Volvos, mine is an '81, were notorious for overheating. The after market replacements were cheap and failed often. I always carry an extra one. The biggest problem is that both the in tank pre pump and the main pump operate off the same relay. Add to that the #12 wire that is used for both fuel pumps and the wire to the fuse panel and you get the pic.
Humbo

Rusty and Nick

Thanks again for the info--- I think my wallet is about to experience another PM purchase.
Cooler solenoid, warmer wallet (from use and less cold cash)

Bud

Every barth owner with a diesel motor should have one of these relays on board at all time. This is the same relay that is known to fail and not allow you to start your Barth. This has happened to me and others. On the Breakaway, it is located in the outside electrical compartment under the drivers window and powers the bus bars needed to run your motor. I checked into a higher rated solenoid with NAPA, but they do not carry one. The thing about these solenoids are they are installed at the factory and then there is more "accessories" added to the electrical systems by owners and the relay is never upgraded to handle the extra load. There are after market solenoids available with higher amp ratings. Do a google search to locate them. I cannot remember where I found them on the internet. But beware of just raising the amp rating...could cause other electrical problems!