My dash light dimmer switch didn't work from day one, so when I was working on the dash last month, I decided to investigate. I removed the headlight switch and found that the dash dimming rheostat was completely gone, further evidence showed it had been badly overheated.
rheostat gone:


overheat evidence:


Link to my write up and conclusion:
headlight switch

I believe that with 25 dash lamps, this is way over the number of lamps this switch was designed to operate. I will be designing a separate dimming circuit in the future.

I too have had the same headlite switch problem and would like to solve it the same way with a double pole rocker switch (headlites & clearance/off/clearance) Also like my dash gauges at full brightness. How did you wire them into headlite circuit bypassing switching? Did you just tie into the headlite switch output?

I'd suggest a solid-stae voltage regulator. Current to the "control" leg is quite minimal.

That said, the resistor (Pot) in my system is capable of dealing with the loads - but it ain't "yer father's resistor".

Yes, I will get you the wire numbers tomorrow. I tied it into the tail/clearance light wire so the dash lamps would be on with either the tail or head lights.

quote:

Originally posted by Rusty:
I'd suggest a solid-stae voltage regulator. Current to the "control" leg is quite minimal.

That said, the resistor (Pot) in my system is capable of dealing with the loads - but it ain't "yer father's resistor".

I will make a switching regulator, no heat.

Do you have a GM dash panel or do you have VDO gauges? That is where we get into trouble, each VDO gauge has one light and the speedo has two, add the heater control and the radio, lots of current.

quote:

Originally posted by beeoh: Also like my dash gauges at full brightness. How did you wire them into headlite circuit bypassing switching? Did you just tie into the headlite switch output?

The inst light wire is #31B and if you tie it to #243, that is the tail light relay wire, the dash lights will come on with either the tail lights or head lights.

If you can see your switch (might be very difficult, #31B is in the middle at the very front of the switch. #243 is the next one over counter clockwise looking at the front of the switch.

Tomorrow I will open the electrical panel and see if I can find #31B there, if so it would be simple as I know where 243 is down there.

HTH

My dash lights did not work either. Pulling the switch one of the connections was burnt. I had a hell of a time getting a working switch, they simply would break or not allow the plunger to engage. I finally got one that worked after going thru about 6 switches (auto zone was great in replacing them)

I would recommend a different set up if you can do it. Next year I may rewire the dash into a simple on off switch. I agree that full brite is best for me on the dash lights. My switch was listed as a chevy/gmc used from 1972 to 1988 my coach is a 98.


Tom

Here is a picture of the front electrical panel and where you could jumper from the tail light circuit to the dash light circuit. Very easy to do, I would suggest the the wire 31B be removed from the light switch but is not really necessary because both the tail lights and dash light should be on at the same time. shorting around the rheostat will not cause any issues.

As usual, this is a Barth Breakaway and YMMV, panels may be different,



Just noticed that the wire # listed is reversed, sorry, #18 is on the left and 31B is on the right

Ed: Do I transfer 31B to 18 or tie them together using a jumper wire ??

quote:

I will make a switching regulator, no heat.

Do you have a GM dash panel or do you have VDO gauges? That is where we get into trouble, each VDO gauge has one light and the speedo has two, add the heater control and the radio, lots of current.

Yes . The aftermarket gages are VDO or S-W (genset fuel level, tranny temp, EGT, boost). The main cluster is stock GM. The other switches are Barth-installed, including, I suspect, the headlight/nav light switches. The main GM fuse panel is pretty much empty, replaced by three installed by Barth.

quote:

Originally posted by carlflack:
Ed: Do I transfer 31B to 18 or tie them together using a jumper wire ??

If yours looks like mine, certainly, you could just move 31B to 18. The place for 31B is still labeled so it would be no problem returning it if need be.

I have no idea why they brought 31B down there, nothing except one wire is on mine, doesn't go anywhere else from there.

BTW, one interesting change Barth made to my '94 Breakway is that the left front outside compartment is storage, rather than the electrical center it is on some Barths. This leads to a spaghetti farm inside the dash, but the extra storage is great.

Two fuse panels are inside the dash, while a third is under the bed alongside the converter. The house 12VDC breaker box is also under the bed.

I still have a spaghetti farm behind my dash AND the spaghetti farm in the outside compartment. I think this electrical panel in the storage compartment is on most 30' and up Breakaway. I would like more storage but it is workable.

quote:

Originally posted by Tom Loughney:
I had a hell of a time getting a working switch, they simply would break or not allow the plunger to engage. I finally got one that worked after going thru about 6 switches (auto zone was great in replacing them)
Tom

It really sucks to have to do quality control for somebody's factory, huh?

I had one of those. No brand name on it, just "Asssembled in Mexico". I had to dismantle it out in the boondocks and make internal repairs. Later, I will replace it with a genuine NOS Delco switch.

NAPA sells two grades of that switch. One is Echlin, and is a quality product. The other one is less than half the price, and is poor quality.

You can also get lights again with a failed switch by jumpering 1 to 9 for the headlights and something else for the tail. Just carry some wire and terminals and stick the jumpers in the connector.

I just completed the removal and cleaning up of the rats nest of wires under the dash on my coach because I could not see the gauges at night. I removed each gauge, found the wires and encased each set into the corrugated wire loom that is in new cars. While at it I replaced every bulb in the gauges and the switches with led's and the improvement is astounding. I chose blue lights for the gauges and white for the switches (led's colors will be filtered by the lens unless it is white ie a green bulb will not be visible in a green faced switch) and they are now bright and still dimmable. My new headlight switch doesn't know it is working except for the headlights and no more heat from the switch housing. I also removed the non-working cruise control switches and built a new dash of 11 ga aluminum in three pieces in case I ever need to go back in.