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Max Hubrich · 10-12-2011, 12:13 PM

I plugged in my power supply for my TST tire sensor monitor a few days ago (into the "Cig ltr" sockets). It apparenty blew something. Both power sockets were then- Dead! I had to "jerry rig" (yes, I "fused" it) a new power multi-plug source to run the GPS, phone charger, etc. I ordered a new power supply for the TST. I then departed Maine enroute to North Carolina.

I found a blown 10 amp fuse on the Workhorse fuse power panel today in New Jersey. It is labeled "MKR LPS" That stands for: License lamps, Body Builder Marker Lamps.

The Newmar 12v panel had nothing blown. I have no running lights, parking lights and no tail lights. The brake lights, and turn signals work fine. The head lights work also. Today I bought a new relay for the Newmar 12v panel, thinking one of the six relays was bad. I changed them out one at a time, no change- still no running lights, tail lights, or parking lights.

This is what gets me. After I replaced the 10 amp blown fuse, the "Cig ltr's" came back to life- big time- WITH 17v's-

. The batteries and all power points I checked are 13.6v to 14.3v.

How's that possible? and what have I missed in getting my running lights, etc, going again?

I can only drive in daylight hours right now-

.

RJay · 10-12-2011, 12:20 PM

Max,
What is the voltage at your batteries?

Max Hubrich · 10-12-2011, 12:37 PM

Chassis Battery (1) 13.5v

House Batteries (2) 13.49v

I'm using the same, new, digital volt meter for all readings.

RJay · 10-12-2011, 12:45 PM

Sorry Max, after re reading your post I see you mentioned the battery voltage.

If you plug anything in the cig ltr will it work? I'd be surprised if the cig ltr will support a load. Call Newmar at 1.800.731.8300 and ask them to email a wiring diagram for your 12 volt system.

Max Hubrich · 10-12-2011, 12:56 PM

I have a small plug in inverter I can try. I used to use it to find "hot spots" for Wi-Fi.
That should absorb any high voltage shock.

Skip426 · 10-12-2011, 12:57 PM

Max; the condition you discribe makes ,no sense at all, and I can see why it's got you scratching your head. An unregulated Alt. is capeable of producing some wild volt readings , but with the motor off and no shore power. There should be nothing in the system to produce anything higher than battery volts. I'm going to tag along on your thread to see what you find, and hear others ideas. Good luck, and when it comes to weird electrical issues like this one your going to need LUCK.

mfire1339 · 10-12-2011, 01:14 PM

Got a solar panel?

Mike

Max Hubrich · 10-12-2011, 01:22 PM

Ray,

I pluged the small 400w inverter into the "new" multiplug adapter (13.4v)and it fired right up.

Then I moved the inverter plug to the original "cig ltr" plugs and "nothing" happened. Those plugs now read 16.4 volts.

Mike,

Yes, I have a small 5w solar panel on the roof.

"007" · 10-12-2011, 04:02 PM

Max, have a look at your 7 pin jack at rear of coach, may have a batt lead cross in plug to other power lead.
Check under coach make sure no wires hanging down over exhaust system.

RJay · 10-12-2011, 04:27 PM

Max,
I wouldn't worry too much about the 16+ DC voltage, it's probably an induced voltage and collapses under load as you have discovered.

Instead of using the voltmeter to test the fuses do you have a 12 volt test light you could use? If so test the fuses on the panel that control your our outside running lights.

ottffss · 10-12-2011, 05:22 PM

What RJay said.

Test the volts under a load, that is stick a light bulb in the outlet and test the voltage across the light bulb.

It could be a high voltage no ampacity reading from the solar panel. Try testing at night to confirm.

Max Hubrich · 10-12-2011, 05:54 PM

RJay,

I have pulled every fuse out and "ohmed" each one.

I'll limp into NC in the daytime. We have a great Automotive electrical guy there named "Luke". He can sort it out for me. I've tried calling him all day but alas, he puts the phone on hold when he gets too busy-

.

I remember back in '98 after a big flood in Eastern NC, I was at his shop and he had a beautiful, brand new, white extended cab, S-10 Chevy. I said "Luke" whats wrong with that new truck? He said "It got flooded at the dealership and it's been at three dealers and they can't get it to start. They replaced the computer two times, all new engine wires, etc, etc- now I've got it. Well, what I know is this, I'll look at something else!" He then said "I have an idea it might be in the new "key reader" system manufacturers just started using". I went back by his shop in a few weeks and he just smiled and winked, "yup that was it"! A new key reader in the steering column and she started right up.
Luke has a reputation for hundreds of miles around Goldsboro, NC. Every mechanic in his part of the country has heard about "Luke". The name of his company is "Lukes Automotive Electric- Hwy 581"- They just built a new Super Wal-Mart (Princeton NC-HWY 70) right down the road from him. Great stop for a quick repair job if you have an electrical problem.
He has severe arthritis, but don't worry, he has a long time Latino that works for him that is as good as he is, and he carries the work load for Luke.

Just don't try to call him-

.

I'll keep ya'll posted

Max Hubrich · 10-12-2011, 06:11 PM

Yup--

I just checked the voltage, in the darkness of this night, and it's .03 volts. The solar panel is the culprit. That part of the 17v problem is solved.

Great work-

Thanks Guys,

Norm4015 · 10-12-2011, 06:33 PM

A blown Marker Light fuse is usually caused by a short in the toad's wiring or in the cable between the motorhome and toad. Disconnect the cable at the rear of the motorhome and replace the marker light fuse and try the lights. If they now work you have eliminated the motorhome. Remove the ends of the cable between the MH and toad and repair the short.