HOW-TO-> fix 03-04 SVT Cobra Gauge lights

John M

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did mine not to long ago and since it was apart I did the boost guage mod, lights didn't work the first time talked to speedhut for about a week just to answer my question of what the voltage should be coming out of the inverter, if you have good pwr to the inv + ground and ohm the sheet for the lights and there all good. all it can be is the inv, any way he sent me a new one and it worked just fine, ill post the inv specified ac V you should have coming out of the inv when I get home
 

hex99CobraConv

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It's still available from Speedhut.

Part: A-Invert-04

Did mine a few months back and it's been working great. Just follow the instruction posted in this thread on page 1.

Rick
 

Fred'S'nake

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Yes this is an old post but the listed inverter is now disconned. This is the new part from Speedhut: Part: A-INVERT-05. Can anyone verify this will work without destroying my cluster?
 

knightrida5

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Any updates on this? Anyone find another place for inverters or still using speedhut? My cluster is not lighting up now and seeing for updated solutions.
 

masonic sn95

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Any updates on this? Anyone find another place for inverters or still using speedhut? My cluster is not lighting up now and seeing for updated solutions.
I just ordered my inverter ..I'm gonna follow these instructions..ya there is a new part # the other inverter is discontinued..let's hope it fixes my problem..running out of patience
 

99Venom

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I just ordered my inverter ..I'm gonna follow these instructions..ya there is a new part # the other inverter is discontinued..let's hope it fixes my problem..running out of patience

I'll be interested to see how it works out for you. I'm in the same boat and wondering if the current part (#A-INVERT-05) still works with our factory gauges? It does have it's own dimmer switch included.
 

bullitt2735

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My cluster just went out early this morning on the way to work :-(. I ordered the new 05 version. I'm assuming the dimmer is just a simple pot and if I cut it off and jump it, it will be full power. Then I should be able to dim with the factory pot adjuster. I will see and update once I get a chance.
 

99Venom

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I talked with speedhut today about the inverter. The tech support guy was not 100% sure the A-INVERT-05 would work with the stock Ford gauges. He did say it required a 12v input and had a 120-150 VAC output. The dimmer switch is the question mark, as you could cut it out and wire it to the factory dimmer switch, as long as the factory switch varies voltage and not resistance.

There was another single inverter on their site A-INVERT-03 but it looks smaller and only has a 100 VAC output, but I'm not sure if that's enough for the factory gauges? But it doesn't have the dimmer switch.
 

bullitt2735

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The 05 version came in today, but my gauges started working again the day after i posted them. So unfortunately I will not be updating everyone on how it will work with the pot on the 05 version. I will keep it as a spare for now and next time it goes out I will install it with the 05 version with a write up.
 

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99Venom

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anyone else on this topic? Does the -05 inverter work and what is the procedure for the extra dimmer?

Yes I am following this topic too as my backlighting does not come on at all anymore (I'm using the digital speedo at night for the time being). I believe that -05 inverter is the correct one, but I do not know how to wire up that dimmer as our gauges already have it built into the headlight switch.
 

jfletch87

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Does anyone know the output of the factory inverter? Apparently, A-INVERT-05 is 120-150 VAC and A-INVERT-03 is 100 VAC, but whats A-INVERT-04(looks like its the one that worked as a replacement)? And whats the frequency of the output? If I can figure out what the VAC and Hz is supposed to be for the cluster I can just make one. The Ford wiring diagram doesn't give these details.
(I work in a electrical engineering lab)
 

99Venom

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Judging from the pics on the first page of this post I don't see any specs printed on that inverter, but we don't see the back side of it. I imagine that's probably the only way to get the specs.

I called Speedhut and they said they discontinued the A-INVERT-04 because some were melting. The output of that inverter was 140-160 VAC. I asked about the A-INVERT-05 and they said you can jumper the two wires together for the dimmer if you don't want to use it. The inverter will see full power from the headlight switch and that can be used as the dimmer. So that sounds like the -05 will work with that simple modification.
 

99Venom

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Here's an update. I installed the A-INVERT-05 inverter on my gauges last night. I soldered everything up per the instructions on the first page of this post. I called Speedhut and asked them what I could do with the dimmer. They assured me, multiple times, I could clip it off at the inverter and it would not create an open circuit. It didn't make sense to me, but not knowing the internal circuitry of the inverter I have no way of knowing for sure. Plus, my electrical knowledge is pretty basic.

I did that, and installed everything, but still no gauge lights. I'm not sure what went wrong, but I did leave myself plenty of wire so I might just take it all apart, clip the plugs off and re-solder it again. I checked the soldered connections and they were nice and tight, so I don't think that's the issue, but I'm not sure what else to try.
 

99Venom

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The latest and greatest update - the A-INVERT-05 works! After trying multiple things with no lights, I found someone local that fixes gauge clusters and can diagnose and repair circuit boards. Through some deep digging he found a bad resistor on my circuit board directly before the power plug for the inverter. Just so you know, the resistor hadn't completely failed, it just had a small voltage disruption and apparently it was enough to kill my back lighting. I had a spare working cluster so he de-soldered the same resistor on that board and soldered it onto mine and viola - it worked. This with the dimmer switch cut off of the Speedhut inverter. Hopefully this helps some people out.

This guy is local to me, but you could always ship him your cluster. He was fast, easy to work with, and not expensive at all. He specializes in GM but after I sent him a few pics and he researched it a little, he had no problem diagnosing my issue. Also, if my board turned out to be not repairable, he can transfer mileage and PATS over to a used cluster as well, so either way you can get your lights back.

His name is Bill, he saved my ass: http://www.mainerepair.com/
 

OPENRUP

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The latest and greatest update - the A-INVERT-05 works! After trying multiple things with no lights, I found someone local that fixes gauge clusters and can diagnose and repair circuit boards. Through some deep digging he found a bad resistor on my circuit board directly before the power plug for the inverter. Just so you know, the resistor hadn't completely failed, it just had a small voltage disruption and apparently it was enough to kill my back lighting. I had a spare working cluster so he de-soldered the same resistor on that board and soldered it onto mine and viola - it worked. This with the dimmer switch cut off of the Speedhut inverter. Hopefully this helps some people out.

This guy is local to me, but you could always ship him your cluster. He was fast, easy to work with, and not expensive at all. He specializes in GM but after I sent him a few pics and he researched it a little, he had no problem diagnosing my issue. Also, if my board turned out to be not repairable, he can transfer mileage and PATS over to a used cluster as well, so either way you can get your lights back.

His name is Bill, he saved my ass: http://www.mainerepair.com/
Do you think he could repair a 2004
Cobra cluster?

Sent from my SM-G930R4 using Tapatalk
 

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