Electric 12 Volt Fuse Panel

LJ-TJ · June 02, 2010, 03:49 PM

This is a picture of the fuse panel as you see it under the dash

LJ-TJ · June 02, 2010, 03:52 PM

This is the same panel turned around. This is for a 1975 Winnebago.

LJ-TJ · June 02, 2010, 04:02 PM

Notice: The Top post is for the Ignition and Accessories
The Bottom post is for the Ignition and Accessories.

LJ-TJ · June 02, 2010, 04:07 PM

Ooooops D:oH! The Top post is for the Battery and Accessories

The Bottom post is for the Ignition and Accessories.

Mytdawg · September 30, 2014, 11:09 AM

Well I'm going to put this here for lack of a better idea. If we need to move it, please just let me know. Thanks!

Here's the problem. All of mine is hot all the time. All the fuses and both the upper and lower posts are on constantly. Except for the bottom two fuses. Neither one of those are ever powered up, ignition on or ignition off. I'm going to guess this is the beginning of my wiring nightmare. It looks pretty much like that, except for the scorch marks.. , now the question is where should there be power when ignition is off vs. on? Someone has jacked this thing 14 ways from Sunday...

I don't see a jumper between posts or anything obvious. My guess is it's probably backfeeding from one of the many bad idea splices but I can only stand on my head under the dash for so long before I get woozy.

xerofall · September 30, 2014, 04:24 PM

Thanks for the info... I thought I was going to have to run a set of wires/fuse box from the battery directly in order to add a few things like a small fan, GPS, CB, etc...

DaveVA78Chieftain · September 30, 2014, 07:23 PM

74-75 Stock setup (power source)
Radio, Ign ACC, Heater, Horn - Ignition switch ON, Start and ACC (light blue wire post)

T SIG-GA Brk Warn - Main power feed (IGN 1) from ignition switch (VR, Ballast resistor [run], Ignition module power)

RUN LPS, BATT ACC, Int LPS, Ext LPS - All feed from Headlight switch (tail lamp circuit; black wire post)

INST LPS - Headlight switch dimmer

Same for most years but may be some minor variations

Dave

Mytdawg · October 01, 2014, 08:14 AM

Quote from: xerofall on September 30, 2014, 04:24 PM
Thanks for the info... I thought I was going to have to run a set of wires/fuse box from the battery directly in order to add a few things like a small fan, GPS, CB, etc...

There are rules about power draw. The stock box can only supply so much power (and then you get scorch marks or worse). Another power block is not a bad idea. You "should" be able to run the things you mention but you want to make sure you don't overload circuits. Just like in a house you don't want to exceed the rated amperage of a given circuit.

http://www.the12volt.com/ohm/ohmslawcalculators.asp

Thanks for the information Dave (as always). I'll try to reverse engineer it as best I can. I'll probably be back with more questions when I get to another decision point. Winters coming, probably be back in mothballs soon.

xerofall · October 01, 2014, 11:19 AM

Yep, a small fan and hard wiring the GPS shouldn't be a problem. The CB turns out, is already wired up someplace else.

Mytdawg · October 01, 2014, 12:18 PM

I keep thinking for the price of a Bic lighter I could just make my problem go away. W% But for now I'll work on removing all the non factory wiring as best I can then try to reconnect all the original functions one at a time. Shouldn't be much harder than uh, trying to put a jigsaw puzzle together with no picture.

Hey, I got the blower fan working. There was not one connection wired right on the switch. All 3 were on the wrong posts. But I had to install a toggle switch between the fuse box and the relay for now because IT WAS ALWAYS ON!. sigh.

DaveVA78Chieftain · October 01, 2014, 10:27 PM

If you do not have the chassis manual, there is a 74-75 and a 76-77 chassis wiring diagram in the Member area. Will make some of this a whole lot easier.

Dave