2002 Mountain Aire 38 foot gas Batt Boost circuit blows fuses

[mmstadler]

Hi all. My Battery Boost circuit blows fuses and I can't use my battery boost to start engine. Once the fuse blows power to the BIRD is lost and my engine battery won't stay charged when in storage. I do not know if it is the courtesy light circuit causing the short or the Boost circuit since Newmar tied the two together. My question is: where are the courtesy lights located in this year and model? Thanks, Mike

["007"]

Welcome to the forum and irv2.
Couple of links for you 12v battery system and 12v wiring system for reference.

2002 Brochure and Owners Guide.

Courtesy bedroom maybe bath and near kitchen area.

In my signature below are three link related to your Newmar.

The wiring of Bird in in the battery link provide and also in three links for gas coach.

If the coach is plugged in while in storage the Bird system will charge all your batteries as long as the battery cut-off switch is on, in use.




If you have a Workhorse chassis this is the fuse panels under dash panel.

The courtesy light fuse should be near the load center 12v fuse panel.

There is a 5 amp fuse on the isolating solenoid, LEFT HAND SIDE, in boost button circuit if you look at Bird wiring.

How did you arrive at the courtesy light tied into the boost circuit?

[chuckinthebus]

Mine in an 06 EXDP look like step bumper tag lights.
http://ts1.mm.bing.net/th?id=H.45466...=126&h=132&p=0

[mmstadler]

Thanks to both of you for the quick replies. We just bought this unit (2nd MAGA) and did not know that THE BATT BOOST switch did not work until my battery went dead a couple of weeks ago and I could not TIE IN the coach batteries using the switch. I do have all the books and manuals for this rig, but full 12v coach/chassis schematics were not available. I was a Service Manager for a local RV dealership for 4 years a few years ago and this was our top of the line gas rigs that we sold. That being said, we never had much luck with Newmar's tech support on electrical issues, but they were still better than most other MFGs.
To answer youir question about the courtesy lights. Newmar tied them in with the batt boost power feed on most of these unit and upped the fuse rating from 5 to 7.5 amps. That is reflected in my books, but every model seemed a little different as the "where" they placed the courtesy lights and "how" they routed the wiring.
My books show the Batt Boost switch with only having 2 spade terminals to it,BUT I have three with the 3rd being a "white" (ground?) that seems to be a dead short through the switch to the power feed terminal. I am suspecting this switch to be bad.
Do any of you have 3 wires to your Batt Boost switch? Also does
anyone have a source for this switch outside of Newmar? Thanks much, Mike

["007"]

You have many sources in this link you have to check the links provided.
Tap on the picture for ordering details.

[mmstadler]

Thanks much for the help. I'll post a follow up on my issue once I have a confirmed good repair. Mike

[mmstadler]

I used an Ohm meter (DVOM) and checked the Batt Boost switch with the wires hook up, disconnected across the spade terminals and the white wire that shouldn't have been there. The switch worked as advertised WITHOUT the white ground wire hooked up. My inside courtesy lights worked properly and the BIRD started to feed 13.4 volts to my chassis battery. As I mentioned earlier, we just bought this unit and don't know the history of it. I'm suspecting that the Battery Boost or BIRD never worked properly. I'll follow up in a few days if my systems start acting up a again, but for right now, everything works!
If anyone else has a problem with their Batt Boost, Courtesy lights, engine start battery not charging when the unit is plugged in or you keep blowing the 7.5 amp fuse up front in your Power Distribution Center.
CHECK your Boost Switch on your dash for an extra, unneeded ground wire. Thanks again for the feedback and help.. Mike

["007"]

All you need to do now is figure out what is not working on the other side of that ground.
As long as coach is now plugged in the Bird System will keep all your batteries charged and you will be good to go.
Thanks for the follow-up.

[mmstadler]

That's true. I'm in the process of building some ATO fuse leads (1/4" spade terminal ends) to run a Tone Generator type short circuit tester from that ground or shorted wire to determine what/where it goes to. I bought one of these for our shop (many years ago) and it was a great help in locating shorts and opens since most RV mfgs just ran wires anywhere without schematics. Thanks again 007.