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Tue Feb 24, 2004 5:56 pm

I posted a msg on Feb 12 about an electrical problem and kind of got sidetracked with my question. Ratwell answered that my clicking noise that I heard from a relay was probably due to a low battery and the clicking or buzzing was the relay not getting enough electricity to do its job. That is exactly what was happening.....THANK YOU RATWELL !!

But what brought me here in the first place and what I didn't explain thoroughly in my first post was that my electrical problem stemmed from a dead battery. I have just replaced the battery and now I know why the old battery went dead. The battery idiot light was on. Remember, there is a new battery in the bus. Once I got the new battery connected, I went up front and turned on the ignition. The idot lights in the cluster all lit up and appeared to be working fine. I start the engine and all of them go out like they should. When I shut the engine off and take the key out of the ignition the battery light comes on and stays on. This has apparently happened while the bus was just sitting, as the last time that I used it (approximately one month ago) when I shut it off then, I didn't notice the battery light coming on or staying on. It must have happened all by itself and that was what ran down the first battery. Does anyone have any thoughts on where I should start looking........I realize something must be shorted out somewhere, but I'm hoping that someone else has run into this before. Thanks for all your help.

Tue Feb 24, 2004 6:53 pm

The battery light gets power from the ignition switch and is grounded by the alternator. When the key is turned on and the engine is off there is 12V across the idiot bulb (flowing from the switch to the alt). When the engine starts and the alternator starts up there is no voltage drop across the bulb (say 13V on each side of the bulb) so it doesn't light. When the alternator fails to charge the battery and the voltage drop is just enough the resistance of the bulb is overcome and it lights up telling to run to your copy of Muir for advice.

I would guess that you've got a faulty igntion switch or a wiring fault with the bulbs and it's wires if the bus otherwise works. If the battery is running down check the voltage at the coil (terminal 15 vs. ground) after you remove the key to see if it's still getting power.

Tue Feb 24, 2004 7:49 pm

aniforos wrote:
But what brought me here in the first place and what I didn't explain thoroughly in my first post was that my electrical problem stemmed from a dead battery. The battery idiot light was on.

Check voltage regulator by unplugging it. Idiot light out? Voltage regulator contacts may be stuck closed. Replace. Normally if there is any question about the ignition switch itself, it would power the oil light and the gen light and the coil without your consent.
Colin