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1978 Royale Monitor Panel [message #206249] Sun, 28 April 2013 17:01 Go to next message
Richard Andis is currently offline  Richard Andis   United States
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Registered: January 2013
Location: HELL Paso, TX
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Does anybody have or can they direct me to a schematic for the Monitor Panel on a 1978 Royale. Perhaps a simplified diagram on how the tank level system works.

Currently the the 1/4 light is stuck constantly "on" (lighted)regardless whether any switches are pushed. Whenever I push any switches to check tank levels I get an "E" (1/4 remains on). Not sure what the actual content levels are. The fresh water tank monitoring had been working fine before and during most of our trip. I know I have some broken wires on my black tank and most of the wiring under the generator is a mess (Lots of wire-nuts and electrical tape). I'd like to know what it is supposed to look like before tearing into it.

Also, how do you access the wiring behind the monitor panel? There are 4 small screws holding the metal plate to a wood frame. Do I remove those? Looks to be a very small square drive on the screws.

This is a 78 Royale

Edit:
From my observation there appears to be 8 "buttons" (contacts) on both the black and grey water tanks. 5 of the buttons are used. I'm assuming that the liquid in the tanks complete the current paths and the Monitor panel sorts out the levels (higher the button, fuller the tank.


Valhalla - 1978 GMC Royale rear twin [SOLD]
Walküre - 1974 VW Thing (Toad)

[Updated on: Sun, 28 April 2013 17:33]

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Re: 1978 Royale Monitor Panel [message #206260 is a reply to message #206249] Sun, 28 April 2013 19:17 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
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Registered: January 2004
Location: Menomonie, WI
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My 78 Royale has much the same problem. In my case it is TP that is hanging up on the probes inside of the tank and conducting enough electricity to get a false reading. When I have that problem, instead of dumping on the way our of a campground, I will fill the tank to 1/2 full...or empty it to 1/2 full and drive it. The sloshing around of the tank content usually washes (Ha!!) the probes clean. If that doesn't do it, I will dump the tanks, then add enough clean water to 1/2 or 3/4 full and do some quick starts and stops on the road in front of the house. (we live on a dead end street) That always does it. JWID

Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: 1978 Royale Monitor Panel [message #206284 is a reply to message #206260] Sun, 28 April 2013 22:40 Go to previous messageGo to next message
Richard Andis is currently offline  Richard Andis   United States
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Registered: January 2013
Location: HELL Paso, TX
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I'd be curious as to why you should get any reading unless you push the appropriate switch. Unless you push the switch to tank 1 or 2 there should not be any voltage to the circuit at all. I'm only guessing at this point because I still haven't seen a schematic.

Valhalla - 1978 GMC Royale rear twin [SOLD]
Walküre - 1974 VW Thing (Toad)

[Updated on: Tue, 30 April 2013 09:30]

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Re: 1978 Royale Monitor Panel [message #206402 is a reply to message #206284] Tue, 30 April 2013 09:30 Go to previous message
Richard Andis is currently offline  Richard Andis   United States
Messages: 261
Registered: January 2013
Location: HELL Paso, TX
Karma: 0
Senior Member
Anybody?

Valhalla - 1978 GMC Royale rear twin [SOLD]
Walküre - 1974 VW Thing (Toad)
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