Testing gauges with new voltage limiter

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70Duster340

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I have the cluster out of the car, and would like to test the new voltage limiter that I installed. This is a Rallye dash. At the risk of seeming stupid, how can I wire up the gauges using a 13V battery and a fuel tank sending unit? I'm not even sure I wired the limiter properly.

Any help is, as always, greatly appreciated!
 
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Look at your FSM. The electrical diagrams show the eight pins and the rest of the circuit. You will see where to attach your 12v power source (and don't forget to ground the cluster). Then with 12v applied you will see which pin to ground (goes to the senders, gas, temp) and that will peg the gauge and tell you it's working.
 
Murray said:
Look at your FSM. The electrical diagrams show the eight pins and the rest of the circuit. You will see where to attach your 12v power source (and don't forget to ground the cluster). Then with 12v applied you will see which pin to ground (goes to the senders, gas, temp) and that will peg the gauge and tell you it's working.
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Unfortunately, I don't have a FSM for the Rallye dash. I do have one on CD for my Duster, but it doesn't include a wiring diagram for the Rallye dash. I have ordered a color wiring diagram specific to the Rallye dash, just waiting for it to arrive.
 
There were slight differences in rally dash wiring in 67-9 cudas, that may be the case with yours also.
70Duster340 said:
Unfortunately, I don't have a FSM for the Rallye dash. I do have one on CD for my Duster, but it doesn't include a wiring diagram for the Rallye dash. I have ordered a color wiring diagram specific to the Rallye dash, just waiting for it to arrive.
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I have a sensor tester I made that I can loan you if you want. You just need to apply 12 to the dash.

E49128C3-2D65-4A0C-92A2-F1638DFC9AFD.jpeg
 
I agree, that should be in the "how to" section. Right now my biggest concern is if I have the limiter installed properly. I really don't want to burn anything up, or fry any gauges or the PC board.
 
You don't need a diagram, just look at the rear of the cluster. Can you post a photo of the cluster, a CLEAR photo?

Go by the harness wire colors to identify sensor wires and "key" power coming into the cluster

There are three terminals to your fuel gauge.

1....one goes to the fuel gauge sender pin on the PC board. ID this by harness wire color
2.....One is power coming into the old IVR from the key. That also you should ID by color
3....The third pin is the IVR output which jumpers to the other two gauge power studs. That should be easy to follow

If "you don't think it's wired correctly" you better figure out how to check because you may be burning up some hard to find gauges......................
 
Post photos of the limiter hooked up. And what you did to the internal limiter to isolate it from the circuit
 
4spdragtop said:
There were slight differences in rally dash wiring in 67-9 cudas, that may be the case with yours also.
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The printed circuit boards on rally panel never changed (other than blue or green color). With the instrument panel on the workbench and the wiring harness is in the car, factory wire casing colors are irrelevant.
Understanding these circuit boards is about as simple as getting the rabbit to the Trix on the back of a cereal box. All 3 of the thermal gauges have a post in a common copper trace. That is the 5 volt trace. The gauges each have another post in a trace. That is the sender side of the gauge. Only remaining question is the 3 post fuel gauge. which is sender and which is 12 volt? I'll answer that question. The pin at 12 o'clock/top center of round connector is the sender trace to the fuel gauge. You already see where 5 volts is on the fuel gauge. The only remaining post has to be the 12 volt into the limiter. You can follow that trace back to the pin at about 9 o'clock position of round connector. There you have it.

rally panel circuit board.jpg
 
^^Thanks Red. I don't have a Ralley cluster, so have no reference for this stuff. ^^
 
67Dart273 said:
^^Thanks Red. I don't have a Ralley cluster, so have no reference for this stuff. ^^
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Yeah there are still things we dont know. He says he dont know if he has the limiter wired correctly. I dont know what add on 5 volt supply he is using that isn't labelled where is 12 volt in and where is 5 volt out. The plug in type limiter for standard panel may not be labelled. Are the RTE units connections labelled? More details about what he did do or didn't do about the internal limiter, what add on he is using, pictures, would help us help him.
 
Folks, the limiter is marked properly, my concern is if I wired the limiter properly. I wasn't sure which of the 3 terminals was the 12V feed for the limiter. I am just trying to be sure since it's a Rallye dash and I don't want to burn up any of the gauges.
 
I'm gonna conclude "OK" Make sure the post you have 12V hooked to for the new limiter is actually 12V at the harness connector.

From the RTE page:

AbodyRallyeLimiter4.jpg


AbodyRallyeLimiter3.jpg
 
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I like to put star washers on my ground screws to make sure they “bite”.
 
Any decent fastener's store should carry them. I think places like "Ace Hardware" might even have a few
 
67Dart273 said:
Any decent fastener's store should carry them. I think places like "Ace Hardware" might even have a few
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Yep, what Del said. available at Ace, Lowe’s, Home Depot or about any hardware store. I bought an assortment box at Menards for about $5. Then I spilled it on the floor.....said a few bad words...
 
GRRRRRR, You have a shade tree repair at the circuit board contact pin where 12 volts is. That is totally not needed with a replacement regulator. If the head of that little bolt contacts the housing behind the board, you have a short circuit. There is very little relief behind the board there. Take that screw out and toss it. Take that wire out of the round harness connector and attach it directly to the regulators 12 volt wire with male and female spade terminals. You dont want or need 12 volts going into the fuel gauge anyway.
Internal toothed washers and 10-32 hex nuts just like what is on you amp gauge posts are available at home depot in little orange packages at about 78 cent for 6 to 10 pieces. I have put the ring terminal, toothed washer and hex nut on top of the speedy nut.
Those little screws that attach the board to housing do provide ground paths for light bulbs but they are in piss poor threads , easy to strip out, and really too short for added ring terminal and toothed washer. An actual dedicated ground wire attached under the dash somewhere will serve much better. Again male and female spade connectors so the added ground wire will unplug like most everything else.
 
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RedFish said:
GRRRRRR, You have a shade tree repair at the circuit board contact pin where 12 volts is. That is totally not needed with a replacement regulator. If the head of that little bolt contacts the housing behind the board, you have a short circuit. There is very little relief behind the board there. Take that screw out and toss it. Take that wire out of the round harness connector and attach it directly to the regulators 12 volt wire with male and female spade terminals. You dont want or need 12 volts going into the fuel gauge anyway.
Internal toothed washers and 10-32 hex nuts just like what is on you amp gauge posts are available at home depot in little orange packages at about 78 cent for 6 to 10 pieces. I have put the ring terminal, toothed washer and hex nut on top of the speedy nut.
Those little screws that attach the board to housing do provide ground paths for light bulbs but they are in piss poor threads , easy to strip out, and really too short for added ring terminal and toothed washer. An actual dedicated ground wire attached under the dash somewhere will serve much better. Again male and female spade connectors so the added ground wire will unplug like most everything else.
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You seem to be a bit aggravated, Redfish. I'm just trying to make sure that I have everything set up properly so I don't ruin a totally good Rallye dash. I appreciate the input.
 
70Duster340 said:
You seem to be a bit aggravated, Redfish. I'm just trying to make sure that I have everything set up properly so I don't ruin a totally good Rallye dash. I appreciate the input.[/QUOTE
Yeah, I'm a grumpy old fart. My "reel time"? I need to go fishing.
Switched 12 volts goes to the limiter or regulator, wherever it is located. If you no longer use the original limiter in the fuel gauge 12 volts shouldn't go to the fuel gauge. If this fuel gauge is going to be just like any 2 post gauge it should be isolated from chassis ground just like any 2 post gauge. If you lift your oil and temp gauges you will see where the housing is cut away behind them. They mount to circuit board only. Lift your fuel gauge and you will see a piece of metal on the back of the gauge and a unpainted spot where that piece of metal contacts the housing. That is/was chassis ground for the internal limiter. Simply cover than piece of metal with electric tape. 5 volts will go from external/addon limiter or regulator, to and through all the gauges just like a standard instrument panel. There is nothing "engineering" about it.
If you already opened your gauge to disable the original limiter... fine. Just know that doing so wasn't absolutely necessary. If you dont put 12 volts to it, Dont give the gauge can a chassis ground, Limiter is disabled. 5 volts cant find a complete path to anywhere besides though the gauge and sender.
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Grumpy.jpg
 
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