Battery charging light and MFA fault.

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dozzum
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Battery charging light and MFA fault.

Post by dozzum »

Ive had my clocks apart numerous times in the last 2 days trying to get all of them working at once. Since taking them apart the first time the battery charging light has stopped working and cant get it to work, have tried new LEDs and still no joy even tried the LED in the other way incase the polarity is differant to all the rest but still nothing.

I followed Nates helpful guide and have checked all the voltages with the alternator and battery when running and they are all good 13.8V. Also cleaned all the big earths.

I found on here that someone suggested earthing the blue wire to the alternator and that would cause the light to come on, it did not.

I have continuity from the clue wire to a couple of the pins on the plug that connect into the clocks but didnt know where to go from there.

I also tried taking off the alternator belt and running the engine briefly and the light still did not come on.


The other fault that has developed since I have had the clocks apart is the MFA is not working. The clock is on when the ignition is off but as soon as I turn on the ignition the display fades. I have no idea where to start with this one. I cant see any fuses or relays that relate to the MFA.
This has only happened one of the last few times I have had the clocks apart.

So annoying, fix one thing and another breaks!!! :ire:


Nate
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Re: Battery charging light and MFA fault.

Post by Nate »

sounds like there's probably a crack in the pcb, or maybe a dry joint or two?


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dozzum
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Joined: Tue May 26, 2009 11:29 pm
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Re: Battery charging light and MFA fault.

Post by dozzum »

That's what I was fearing, that's the problem with taking things like this apart, at least I have the important bits working now I suppose.

Cheers for the alternator testing guide by the way.


Nate
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Re: Battery charging light and MFA fault.

Post by Nate »

look over the printed circuit very carefully under very good light, and you will hopefully spot it. when you find a broken track, just carefully solder a thin wire to each end of the section with the break. i did this on my bro's R21 when it started using the fuel gauge as a headlights on reminder. bit fiddly, but not too bad


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dozzum
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Re: Battery charging light and MFA fault.

Post by dozzum »

I'll have a look but i'm not holding out too much hope even if I do find it my soldering skills are aweful.


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dozzum
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Re: Battery charging light and MFA fault.

Post by dozzum »

After refitting them fully into the dash the battery charging light started working but the headlight indicator and speedo failed.

Then earlier today It all decided to start working again, MFA included.

its almost as if its just reset itself.

Is there some kind of ecu in the circuitry that controls the whole thing or is it all just simple circuits?


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