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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Branderson on June 26, 2020, 08:31:45 AM

Title: Blinkers are on and I don't know why
Post by: Branderson on June 26, 2020, 08:31:45 AM
I've had my 74 MCI parked outside my house for a week now and just today noticed that my passenger blinking lights are on (not blinking)  There is one above the steering wheel and one on the back and there is a small light on the passenger mirror.

It's possible I missed it before but I really don't think so especially since I washed it and would have seen it up close.  Does anyone know a reason why that light would stay on?

What's weirder is I don't even think those lights are on when I have my running lights on.  Furthermore, I have the starter batteries and the house batteries turned off.

I'm about to crank it up and head to the camp ground.  One, I hope I didn't drain the batteries but I guess if it starts, I will see if anything changes. 
Title: Re: Blinkers are on and I don't know why
Post by: richard5933 on June 26, 2020, 08:52:10 AM
Quote from: Branderson on June 26, 2020, 08:31:45 AM
...What's weirder is I don't even think those lights are on when I have my running lights on.  Furthermore, I have the starter batteries and the house batteries turned off....

Is your 12v power converter/battery charger turned on? Generator battery? If so, you might have something crossing over.

Otherwise, you have quite the mysterious power source - all batteries off and lights still on.

If truly no DC circuits have power coming to them, then the only other thing I can think of is something crossing over from your 120v system, which of course is not good.

I'd start following the wiring harness looking for a problem area before you let the smoke out.
Title: Re: Blinkers are on and I don't know why
Post by: Branderson on June 26, 2020, 12:45:26 PM
Well when i turned the power on and started the engine,i flicked the blinker on and off and that seemed to do the trick.

I called my uncle who did a lot of the wiring and he said the blinker is direct wired to the 12v starter batt. But if i try to turn on blinker now, nothing happens. (I have main starter batts switch off and engine is not running)

I just dont get how a blinking light can come on continuous on its own.
Title: Re: Blinkers are on and I don't know why
Post by: jap42 on June 26, 2020, 12:48:17 PM
You might have 110V shorting to the chassis. Unplug your shore power and turn off all sources and see if they go out.

Or take you shoes off and touch the outside of the bus, that will tell you quick too.  ;D (Please dont try this, use a volt meter)

I would continue to look for a chaffed wire in your 110V system.
Title: Re: Blinkers are on and I don't know why
Post by: richard5933 on June 26, 2020, 03:24:43 PM
The lights blink when you activate the turn signals because the flasher relay makes them blink. A solid 12v is fed to the flasher relay, and it outputs intermittent 12v. The only way I can think of for the lights to be on continuously from 12v would be for the flasher to fail in the 'on' position. But, that would still require 12v to be fed to it through the turn signal switch.

I'm leaning towards a short somewhere.