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I removed the factory gauge cluster from my '91 mustang GT and now it seems that my alternator is not charging the battery. Also there is a constant beeping coming from the dash board. Does anyone have any similiar issues and suggestions on how to take care of this issue?
 

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Tbere is a circuit , what works tbru the instrument cluster , that excites a signal to the alternator , thus making it charge .
You are going to have to replicate this , without your cluster .
 

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correct

the bulb in the cluster, is required

therefore you must put a load in your setup
 

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Were you able to resolve this? I am having similar issues.

Factory load is the bulb AND 510ohm resistor in parallel going to the alternator. I am going to measure the bulb resistance tonight.

Then use formula:

1/Resistane total = 1/510. + 1/ bulb resistance

This should help determine the correct load required. .... I Think! I am no electrical engineer.....
 

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On the other hand a guy on stang net just wires in a 560 ohm 1 watt resistor and it works great.

Confused!
 

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Thanks, yeah I first searched there. They didn't describe what resistor needed to be placed in line with the wire jumping, only that the had a 'jumper' for the job.

I ended up wiring my own harness up in the engine compartment anyway. Bypassing the factory lines. A 560 ohm resistor was WAY too much and didn't allow 'exitation' of the diodes in the alternator. I took it out and I get 14.7 volts, which seems a tad high.

The equation 1/R total = 1/3 ohms bulb + 1/510 ohms for the factory dash would suggest a 2.98 ohm resistor in my wiring would be best. I am going to add a 3.3ohm 1W resistor and see if that drops my alternator down to 14.5 volts or so.

(This shared for future guys trying to make their installs work)
 

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Have you read how the reg works?

The bulb and resistor are powered by the ign switch

The only way the bulb is going light is if there is a ground

Now consider the bulb is always getting power but when all is working the bulb is not lit

There is a switch in the reg!!
 

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I read the diagram from TMOSS but don't understand how the circuit of the regulator works.

I skipped the factory wiring and wires it myself. It works fine with a 3ohm or 510ohm or no resistor.

My output voltage is 14.7 volts regardless of what I do to the exciter wire unless I give it no voltage of course.

I skipped the bulb totally as there is no bulb to light up on the Dakota Digital dash assembly.
 

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I think the reason the 510ohm resistor didn't work was that my alternator connectors had an intermittent connection. Not sure but I replaced them with new and now as I mentioned ANY resistance between 510 and zero seems to work....
 
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