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Discussion Starter #1
I installed the dash below in my 1993 LX. Looks awesome but alternator doesn't work.

Dash Pic:


I realized that I needed to hook up/ splice wires for the exciter circuit now also (bottom right corner). Picture below from TMOSS:


Here is a picture of the back of the OEM Dash Cluster. Nice that it is so easy to see when comparing to TMOSS's diagram.


So, I clipped the wires light green/ red and Red/ green as TMOSS shows and is confirmed by the OEM Dash above. Harness clipped here:


I don't have a picture of the wires on the chassis side/ dash side, but I connected them with the OEM original 510 ohm resistor between them.

(IMAGINE PICTURE HERE....lol)

The alternator doesn't charge however. Of course it did before I started the project :smile2:

When my car is in KOEO mode I checked the three wire connector at the alternator (3G alternator - upgrade from 1994). I have 12v at the yellow wire and 11.9v at the green/red excite wire.

With Key OFF I have 12v at the yellow wire and 0 volts at the green/red excite wire.

What voltage should I be seeing at the green/red excite wire, anyone know? Dakota Digital tech line was called and they had no idea what to do. They'd heard of the problem but didn't address it in the instructions. LOL Very Sad support here with something that EVERY FOX Mustang install will experience.

I can't imagine that I fried the regulator as the install was done without the key in the ignition. But I am about to take it to a parts store to get tested. I don't believe there is anything wrong as it worked PERFECTLY before the install.

Any thoughts or advice from those who've done the FLORIDA 5.0 Gauge Dash Install? I know this is a common problem but I've not found anything other than connecting these two wires as I've shown with the resistor between them.

HELP Please!! Thanks!! :grin2:
 

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Discussion Starter #2
A guy on Stangnet.com just soldered in a 560ohm 1 watt resistor into the green / red wire from his alternator three wire connector and ran it to his ignition power wire on his IAC harness and it worked.

I may try this too or another ignition powered wire in engine bay. Maybe I have a problem somewhere in my OEM harness or something. STILL I got 11.9v to the green/red wire on the connector with KOEO... maybe that's TOO much?
 

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Alternator checked out fine... I sure hope somebody can tell me the voltage at the green wire of the alternator at KOEO... please!!!
 

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For others in the future.... the 560ohm resistor was too much resistance for tha alternator to become active. I took the resistor out completely. The alternator works great. 14.7 v. ((EDITTED- or so I thought read on))

I wonder if this is too much voltage into the regulator on the green/red wire so I'll get a 250 ohm 1W or so and try it. I've heard you want 3v there. For some reason with the 560ohm resistor I have 0.6v on that green wire which clearly wasn't enough juice to get it rocking.
 

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Discussion Starter #5
Still learning here.... I put spade connectors on that exciter wire so I could change out the resistor as I wished.

I run it perfectly (volts a tad high at 14.7v constantly, not just at startup) with NO resistor right now. When I add in a 3ohm resistor (the original formula below suggested that was the circuit overall resistance) it had no effect on reducing voltage output of alternator.

Then I tried the stock 510ohm resistor as the Stangnet guy did roughly. Still no effect. Voltage unchanged.

I am now believing that the diodes in the alternator just need any old charge running thru.

Maybe an electrical engineer can explain it to me but for now I will still run with no resistor.


1/resistance total = 1/ bulb resistance + 1/ 510 ohms

Bulb measured 3 ohms and solving for Rtotal gives 2.98ohms. LOL.
 

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Discussion Starter #6
I meant to add that I did install a new set of connectors for the alternator while I was rewiring it. Maybe that's the reason I still had issues even with my new non stock exciter wire earlier.... no earthly idea.

Final summary, I ran all my own wires to run the alternator, skipping the OEM wiring harness completely. Works great. A tad too high in voltage I think?

Sure would be nice to have had the manual cover how to handle this from the get-go. Hopefully they'll fix it for the next printing. Dash works great now that I've figured out how to get the alternator to run. BIG UPGRADE from factory dash and I get lots of compliments.
 

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With the key on 12 volts go to the bulb, the green wire provides ground when the alternator is not charging so the bulb is on. The 12 volts coming through the bulb excites the alternator to start charging, once the alternator starts charging the green wire is no longer a ground it has 12 volts so the warning light is off. The resistor takes the place of the bulb if it burns out so the alternator still gets excited to start charging. The resistor does not have anything to do with the charge voltage.
 

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Thanks that helps.

I took her for a spin with my wife and after about 30 minutes of driving the alternator cut out and I ran on battery voltage to get home. Not sure what is up.

Wondering if I need that 510ohm resistor back in the circuit.
 

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Discussion Starter #10
Thanks. I'll put in that 510ohm resistor and see if that addresses the problem.

Edited- turns out my all custom non-OEM wiring used my radiator e-fan power wire to excite the alternator. Turning off my e-fan turns off the alternator! Easy fix... keep e-fan ON. System works great and I LOVE the Dakota Dash system after over a year and a half of use.
 

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Full field the alt at idle with as many loads as possible

If it bogs down at puts out current

Alt is fine

Look to reg and sense wire
 

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I was thinking about buying one of these for my car along with brand new sensors. Did you ever solve your issue?
 

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I believe the poster omitted the dark green wire from the factory dual black orange wires

This is a common mistake when going to the 130amp alt upgrade

Therefore the poster had 2 issues, and solved 1 with the resistor
 

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dakota digital has a alternator load wire harness that plugs in your cars harness.
one wire goes to number 2 and the other goes to number 14 and this will have your alternator working properly
 

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Hello,

I am experiencing similar issue even though I installed the supplied alternator load wire, which had a inline resistor pre-installed for an ease of installation or so I thought...

Right after installing the dakota cluster, I was stoked to see that everything worked just fine and car was charging at 14.4V. I drove her for about 100 miles before the alternator regulator quit working. My car was running at 12V last few miles. At KOEO, I was reading around 1.35 volts at the green/red wire on the D plug at the alternator. I am supposed to be seeing 2.4-2.6V. Also it would stay at 1.35 after I start the engine. It should be showing battery voltage (minus .25 to 1 volt)

So I went to get my alternator replaced this morning. I got her up and running at 14.4V, but I am still only seeing 1.45V at the green/red wire on the D plug when KOEO. When I got the engine running, I am seeing only 10 Volts at the D plug when the alternator is putting out 14.4V. I am positive this is why my last alternator's voltage regulator fried.

Can anyone tell me if I need a higher or lower ohm resistor? I also am not sure what ohm resistor do I have in my supplied 90-93 alternator load wire. The instruction manual suggests 300-500 ohm resistor. I have also emailed Dakota's technical support.

Thanks!

-Jarvis
 

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Good idea. I’ll do that and report back on the new finding.

Dakota tech got back to me and said the supplied resistor is 300 ohm and he suggested using 250 ohm.

I think factory is 500 ohm? Won’t hurt to try anyways.
 

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Just did this. Got the factory bulb in and I’m looking at 1.42 KOEO on the green/red wire, which means the factory resistor is similar to the resistor I got from Dakota.

I m gonna guess 250 ohm 1 watt bulb should do the trick.

Any ideas where I should be able to find one of those resistors locally ? Computer parts store perhaps? I’ll have to hunt around tomorrow then.
 

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