GAUGES NOT WORKING PROPER

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WAYNE0

WAYNE0

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I have a 67 barracuda. I have a mech. oil pressure gauge in it & i just bought a new water temp. sending unit. When i started it today to see if the water temp. gauge works i noticed that both the water temp gauge & oil pressure gauge were on high. The oil pressure wire isnt hooked up. Could it be a short or a ground issue ? I realy hate wiring lol In fact the amp gauge is the only one working. As for the fuel gauge im not sure. The sending came with the car & looks like it was changed at one time. As for the ground strap i didnt have one so i made one.
 
You need to get this either fixed or disconnected because if gauges are pegged on "high" you will likely burn them up. Replacing those is getting expensive and difficult

If you have a Ralley dash (has an oil gauge) then the regulator for the gauges is built INTO the fuel gauge. You need to pull the cluster if you cannot fix the wiring.

The oil gauge wiring is pretty simple. One wire hooks to the oil gauge sender, goes through the bulkhead/ firewall connector, and leads in to the cluster PC board connector, and then ends up at the sender connection of the gauge.
 
Craven2112 said:
That is one of the best videos I’ve ever watched just on the vintage alone.
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Seeing that video brought back an old memory. Back when my brother and I were running tests on a external IVR for the rally panel, I mentioned another brainchild of mine. I'm on those who turns everything off before turning ignition switch to off. In the case of my 67 Fish, at ignition switch on I got notta. No lights, no sounds. Only the movement of the fuel gauge needle indicated there was a battery in the car.
I sketched out what I called The Rally Centurian. At about 1/8 inch thickness, It attached to the circle of pins on the circuit board beneath or before the factory harness connector. With all connections req'd routed outward parallel with the circuit board no conflicts predicted. A series of green and red LEDs placed somewhere would indicate no only battery present but other key systems go or no go.
Brother said "Interesting and certainly doable. One thing at a time though". Beyond deciding where I would place the indicator lamps, never got back to it.
 
if you have disconnected the stock oil pressure sending unit (which is electrical not mechanical) where is the disconnected wire, which has a bare end where it attached to the old sending unit???
 
str12-340 said:
if you have disconnected the stock oil pressure sending unit (which is electrical not mechanical) where is the disconnected wire, which has a bare end where it attached to the old sending unit???
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When it comes to the oil pressure gauge wire i taped the end of it just to make sure it wouldnt touch any thing
 
I noticed today that the gauge cluster was loose. I tighten all the screws. Does the gauge cluster need to be grounded the dash ?
 
BTW a gauge cluster that is not grounded will cause the IVR to not function, providing full battery voltage to the gauges. This can cause the gauges to read full to over full and burn out the gauges.

A faulty IVR can fail in two ways open or closed.

If it fails open no harm but the temp, oil, and fuel gauges will not work.

If it fails closed, full battery voltage will go to the 3 gauges and can / will fry the gauges.


If your temp gauge reads correctly but your oil and fuel gauge read incorrectly, that suggests either...

  1. The temp gauge is not functioning correctly
  2. The fuel and oil gauges are not functioning correctly
  3. There are wiring / sender issues
 
You are using a mechanical oil pressure gauge not mounted in the cluster, correct???
 
so when you say the oil gauge is pegged on high, do you mean the mechanical gauge, or the gauge or light in the cluster? Does the mechanical gauge indicate correct pressure?
 
The factory electric oil and temp gauges. The aftermarket oil pressure gauge reads fine. I pulled the steering column down and pulled the cluster out. Behind the fuel gauge there is 3 studs. 1 is bare 1 has a black cap and 1 has a wire on it coming from what looks like a resister. The 1 closest to the amp gauge was bare. The middle 1 had the cap and the 3rd one had the wire on it. So what i did is moved the black cap onto the stud closest to the amp gauge. I figured it should be there beside the black wire on the amp gauge. Then i moved the wire from the resister looking thing to the middle stud. Now when i turn the key on the temp and oil gauges do not move. The oil pressure gauge will not work because its not hooked up but the fuel and temp gauges still dont work. Hope this makes sense
 
WAYNE0 said:
The factory electric oil and temp gauges. The aftermarket oil pressure gauge reads fine. I pulled the steering column down and pulled the cluster out. Behind the fuel gauge there is 3 studs. 1 is bare 1 has a black cap and 1 has a wire on it coming from what looks like a resister. The 1 closest to the amp gauge was bare. The middle 1 had the cap and the 3rd one had the wire on it. So what i did is moved the black cap onto the stud closest to the amp gauge. I figured it should be there beside the black wire on the amp gauge. Then i moved the wire from the resister looking thing to the middle stud. Now when i turn the key on the temp and oil gauges do not move. The oil pressure gauge will not work because its not hooked up but the fuel and temp gauges still dont work. Hope this makes sense
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Id look for a Print on it
 
WAYNE0 said:
The factory electric oil and temp gauges. The aftermarket oil pressure gauge reads fine. I pulled the steering column down and pulled the cluster out. Behind the fuel gauge there is 3 studs. 1 is bare 1 has a black cap and 1 has a wire on it coming from what looks like a resister. The 1 closest to the amp gauge was bare. The middle 1 had the cap and the 3rd one had the wire on it. So what i did is moved the black cap onto the stud closest to the amp gauge. I figured it should be there beside the black wire on the amp gauge. Then i moved the wire from the resister looking thing to the middle stud. Now when i turn the key on the temp and oil gauges do not move. The oil pressure gauge will not work because its not hooked up but the fuel and temp gauges still dont work. Hope this makes sense
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NO NO NO!!!

READ this:

RTE Gauge Faq - rte

www.rt-eng.com www.rt-eng.com

Here is how this works:

ALL Mopar gauges EXCEPT the ammeter DO NOT operate directly off 12V. Instead there is a regulator device, alternatively known as the gauge regulator, voltage limiter, IVR, etc, but what it amounts to is the OEM one is a device which works sort of like a turn flasher--it pulses the 12V to form an on/ off pulse that is approximately 50% duty cycle--which mimics approximently 5-6V.

On NON ralley clusters, this is a replaceable, separate little unit which plugs into the rear of the cluster PC board. But READ the link above. On a ralley cluster, the device is BUILT INTO the fuel gauge. The reason the fuel gauge has 3 terminals is, one is 12V from the key, going TO the fuel gauge to SUPPLY the regulator. One terminal is the output of the regulator in the gauge, and it comes out so that it can also supply power to the other two gauges. The last terminal is the sender terminal.

The other two, the temp and fuel, are thus supplied this approx. 6V from the limiter device, and the second terminals of those two gauges. goes to each sender.

BE CAREFUL AND DO NOT **** AROUND

You can burn these gauges up VERY easily, and they are getting harder and more expensive to replace.

All three gauges, fuel, temp, and oil, work the same. With the cluster out, you can jumper 12v to the PROPER board connector pin, and ground, and then rig resistors to the sender terminal of each gauge in turn, which will mimick a sender and give you relative readings. The same resistor, one at a time, on all three gauges, should put the 3 needles in the same place on all three gauges.
c-3826-jpg.jpg


Do a search on here. There are hundreds and hundreds of gauge posts
 
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Sorry i am very stupid when it comes to wiring. Can someone tell me what i did when came to switching that wire from one stud to another ? Where to start and how to find the problem. I have no testers.
 
WAYNE0 said:
Sorry i am very stupid when it comes to wiring. Can someone tell me what i did when came to switching that wire from one stud to another ? Where to start and how to find the problem. I have no testers
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Would you randomly plug a wire into one of the 3 hold on a wall outlet in your house?

2 of them will not (typically) shock you, 1 will kill you.

If you don't know what you are doing don't just randomly plug things into other things.
 
WAYNE0 said:
The factory electric oil and temp gauges. The aftermarket oil pressure gauge reads fine. I pulled the steering column down and pulled the cluster out. Behind the fuel gauge there is 3 studs. 1 is bare 1 has a black cap and 1 has a wire on it coming from what looks like a resister. The 1 closest to the amp gauge was bare. The middle 1 had the cap and the 3rd one had the wire on it. So what i did is moved the black cap onto the stud closest to the amp gauge. I figured it should be there beside the black wire on the amp gauge. Then i moved the wire from the resister looking thing to the middle stud. Now when i turn the key on the temp and oil gauges do not move. The oil pressure gauge will not work because its not hooked up but the fuel and temp gauges still dont work. Hope this makes sense
Click to expand...
The voltage limiter AKA resistor thing I'm assuming your referencing needs that black wire plugged in with it for that **** to work. What I would do is I would first put it back the way it was then go out and pull both of those loose then turn the key on and ground one and see if the gauge pegs
 
MOPAROFFICIAL said:
What I would do is I would first put it back the way it was then go out and pull both of those loose then turn the key on and ground one and see if the gauge pegs
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IMHO

Just randomly grounding things I disaster waiting to happen.


Red dots are 5 to 6 v from the IVR in the fuel guage

Blue dot is the sensor input for the temp guage

Magenta is sensor input for the oil pressure gauge

The hole by the word "Red" and the hole up and to the left of it is for the ammeter.

Yellow OR white is the 12v feed to the IVR inside the fuel gauge. (I don't recall which) the other is the fuel sender feed.


As seen from the back
Screenshot_20230622-230307.png


Front view
Screenshot_20230622-231222.png



This is NOT a resister. It is a capacitor to reduce noise to the radio from the contacts in the IVR inside the fuel gauge.

Screenshot_20230622-232429.png
 
WAYNE0 said:
The factory electric oil and temp gauges. The aftermarket oil pressure gauge reads fine. I pulled the steering column down and pulled the cluster out. Behind the fuel gauge there is 3 studs. 1 is bare 1 has a black cap and 1 has a wire on it coming from what looks like a resister. The 1 closest to the amp gauge was bare. The middle 1 had the cap and the 3rd one had the wire on it. So what i did is moved the black cap onto the stud closest to the amp gauge. I figured it should be there beside the black wire on the amp gauge. Then i moved the wire from the resister looking thing to the middle stud. Now when i turn the key on the temp and oil gauges do not move. The oil pressure gauge will not work because its not hooked up but the fuel and temp gauges still dont work. Hope this makes sense
Click to expand...
First thing to do is move it all back. Without photos, "no idea." The "resistor thing" MAY BE the radio noise suppression and filter cap. You do NOT want to put that on the wrong terminal, as it may damage the internal limiter--if it still works.
 
Took the capacitor wire off. Now when i turn the key on the oil & temp gauges do not move. The fuel gauge is the only one that moves. It doenst move much. It sits on the letter E & moves just to the other side of it. The tank has about 6-7 gallons of gas in it. I took the whole cluster out. As you look at the round wire plug this is the wire order. Starting at 12 oclock & going clock wise--- DARK BLUE EMPTY BLACK EMPTY BLUE ORANGE PURPLE W/ TRACER GRAY DARK BLUE W/ TRACER EMPTY TAN The orange wire being at 6 oclock Ill have to get some pictures. There is a gray wire that is cut off below that. Not sure what that was for.
 
I built a sender simulator box that that I use for troubleshooting gauge issues if you want to borrow it. I will ship it to you.

IMG_0438.jpeg
 
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