My temp guage does not work and I have changed the sending unit but the guage still will not work (nothing happens even when I turn the key on) . I have read the sevice manual but I don't have the test box they say is needed to test the guage. So does anyone have any idea how to test the guage so I can see if it the guage , wiring, or anything else this is all in my 62 Wagon.
Temp Guage issues
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67Dart273
Well-Known Member
First, does the fuel gauge work? They are fed off the same "voltage limiter" a sort of almost voltage regulator that feeds fuel, temp, and if you have it, oil pressure gauges
If the fuel gauge works, the "quick test" is to remove the sender wire, clip lead it to ground, and then go in and turn the key to "run" and watch the gauge. In a very short time it should head quickly to "hot." Don't leave the key on for long, just see what it does.
If this does nothing, it could be the wire is broke right inside the connector, a bad connection going through the firewall, or problems at the dash group connector, or the gauge itself.
Next step is to pull the dash cluster. Use a continuity lamp or meter to check the wire itself.
If that's OK, try jury rigging the dash --plugged in, grounded, and ground the sender wire where it comes off the gauge. Then turn the key to run as before and see if the gauge goes up.
If not, check with a lamp for power at both fuel and temp gauges.
If grounding the sender side of the gauge doesn't cause it to deflect, and if it's getting power from the "limiter" at this point it's probably the gauge itself.
If the fuel gauge works, the "quick test" is to remove the sender wire, clip lead it to ground, and then go in and turn the key to "run" and watch the gauge. In a very short time it should head quickly to "hot." Don't leave the key on for long, just see what it does.
If this does nothing, it could be the wire is broke right inside the connector, a bad connection going through the firewall, or problems at the dash group connector, or the gauge itself.
Next step is to pull the dash cluster. Use a continuity lamp or meter to check the wire itself.
If that's OK, try jury rigging the dash --plugged in, grounded, and ground the sender wire where it comes off the gauge. Then turn the key to run as before and see if the gauge goes up.
If not, check with a lamp for power at both fuel and temp gauges.
If grounding the sender side of the gauge doesn't cause it to deflect, and if it's getting power from the "limiter" at this point it's probably the gauge itself.
I will follow these steps today and keep posted
I don't know if the fuel guage works or not dont have a tank installed as of yet so if you have a quick way to check that while I'm doing the temp that would help me greatly.
I don't know if the fuel guage works or not dont have a tank installed as of yet so if you have a quick way to check that while I'm doing the temp that would help me greatly.
67Dart273
Well-Known Member
You probably have a bad "voltage limiter." The original limiters pulse like a flasther unit. The reason the gauge needles don't "pulse" is because they are slow to react. So with the key on in "run" you should have battery on one terminal, and a pulsing action on the other. If you have an aftermarket limiter with a solid-state regulator installed, you should be showing around 5 - 5.5 volts.
I think Redfish here sells replacement units, and you can "roll your own" with some parts from Radio Sh$$
One approach:
http://www.forabodiesonly.com/mopar/showthread.php?t=75065
another:
http://1962to1965mopar.ornocar.org/ml-instrument-voltage-regulator64.html
I think Redfish here sells replacement units, and you can "roll your own" with some parts from Radio Sh$$
One approach:
http://www.forabodiesonly.com/mopar/showthread.php?t=75065
another:
http://1962to1965mopar.ornocar.org/ml-instrument-voltage-regulator64.html
67Dart273
Well-Known Member
OH!! you are probly right, forgot you were on an oldie.
Here:
http://rt-eng.com/mediawiki/index.php/RTE_Gauge_Faq#A-body_rallye_dash_limiter_fix
tear apart the fuel gauge and "fix" it, then either build your own regulator or buy one from RTE
Here:
http://rt-eng.com/mediawiki/index.php/RTE_Gauge_Faq#A-body_rallye_dash_limiter_fix
tear apart the fuel gauge and "fix" it, then either build your own regulator or buy one from RTE
airkiller
MOPARS Rule
Had same problem with my 74 Duster cluster gauges. Found the nuts that hold the gauge in and make electric contact with the pc board to be loose and the copper trace to be corroded. I would pull the nuts off the back of the gauge and clean the copper with some scotch brite to make hem shinny and then retorque the nuts and see what happens. The limiter maye be fine and with the high resistance connections can not do its job properly.
tear apart the fuel gauge and "fix" it, then either build your own regulator or buy one from RTE
I will follow the atached directions listed thanks for the help the only differance is they are stating fuel guage where my service manual is stating the limiter is in my temp guage. I will try and get picture s today and post what I got/ get.
I will follow the atached directions listed thanks for the help the only differance is they are stating fuel guage where my service manual is stating the limiter is in my temp guage. I will try and get picture s today and post what I got/ get.
Ok here is what I have, please review pics and let me know cause I'm really lost know
1st picture is what was attached to the back of the temp guage and mounted on the back of the dash (what is it and what should it read or do)
2nd front of my temp guage
3rd back of temp guage arrows show where item 1 is located and back of guage states 12V
4th better picture of back of Temp guage
5th show an area where the metal strip has come off the board. I would like to know if might be the cause of my issues. the metal strip is not broken and how/ what can I use to glue it back down. the strip is attached to back guage lights
thanks for any help
1st picture is what was attached to the back of the temp guage and mounted on the back of the dash (what is it and what should it read or do)
2nd front of my temp guage
3rd back of temp guage arrows show where item 1 is located and back of guage states 12V
4th better picture of back of Temp guage
5th show an area where the metal strip has come off the board. I would like to know if might be the cause of my issues. the metal strip is not broken and how/ what can I use to glue it back down. the strip is attached to back guage lights
thanks for any help
67Dart273
Well-Known Member
It appears to me that gauge indeed has an internal limiter.
The 12V terminal would be fed from the ign switch, and the "item" is a condenser/ capacitor and is there to supress radio noise/ static.
It appears the limiter is IN the gauge, and the 5V terminal would be to feed OUT from the limiter to the other gauge(s) such as fuel, oil, anything using a sender.
The 12V terminal would be fed from the ign switch, and the "item" is a condenser/ capacitor and is there to supress radio noise/ static.
It appears the limiter is IN the gauge, and the 5V terminal would be to feed OUT from the limiter to the other gauge(s) such as fuel, oil, anything using a sender.
99% of gauges have 2 posts. The ones with 3 posts have the limiter housed inside. There isn't supposed to be a 12 volt wire to the gauge though. The wires attach to the printed circuit board. The 12 volt wire on your board very likely supplies both the limiter and the park brake indicator. That wire would be hot with switch on and probably not fused.
And we tear apart any gauge, especially when we have no spares.
They are quite fragile. I've received a few with feckin JB Weld all over them. Everything broken and worthless. Good luck through.
And we tear apart any gauge, especially when we have no spares.
They are quite fragile. I've received a few with feckin JB Weld all over them. Everything broken and worthless. Good luck through.
RedFish,
the only 12V wire I have found goes to the Amp guage and it is not linked to the other guages on the cicuit board. so I guess I might have a wiring issues, also as mentioned earlier my circuit board has a section of the metal stripe that has seperated from the board it is not broken just seperated have you messed with this and if so what can I do to secure the metal back to the board.
Thanks
the only 12V wire I have found goes to the Amp guage and it is not linked to the other guages on the cicuit board. so I guess I might have a wiring issues, also as mentioned earlier my circuit board has a section of the metal stripe that has seperated from the board it is not broken just seperated have you messed with this and if so what can I do to secure the metal back to the board.
Thanks
greg r
Well-Known Member
From what I've seen, the 12V terminal is where 12V feeds the limiter inside the temp gauge. The 5V feeds the other gauges, and of course S is for the sender.
Could you connect a jumper from 12V+ to the 12V terminal, ground the case and then see if you get the 5V output at the 5V terminal?
I don't know what resistance values the sender units work with, but if you could get a potentiometer(variable resistor) of say 100 ohms and around 10 or so Watts and put it between the S terminal and ground, you may be able to see the needle move by varying the resistance. That is provided the limiter is working.
All the book shows is some tool with H, M, or L; but it's not much more than a resistance selector box
When there is a short circuit , the melt down occurs at the wealesy point in the circuit. That would be the copper trace on the circuit board. You could run a 12 volt wire directly to the gauge post and attach with a ring terminal but be forewarned ...
If the short still exists, further damage will occur.
I can only speculate as to where the fault is. My experience with these type gauges suggests the root problem to be inside that gauge.
Aftermarket gauges will be the least expensive solution.
If you want those factory gauges to work perfectly just send the entire instrument panel to me and i'll fix it. Warranty on my work is one year but after nearly 6 years I haven't had a come back yet.
If the short still exists, further damage will occur.
I can only speculate as to where the fault is. My experience with these type gauges suggests the root problem to be inside that gauge.
Aftermarket gauges will be the least expensive solution.
If you want those factory gauges to work perfectly just send the entire instrument panel to me and i'll fix it. Warranty on my work is one year but after nearly 6 years I haven't had a come back yet.
OK, Best bet is post in parts wanted for that exact connector. Meanwhile myself and others who are will ing can have a look at their bone pile for a wiper switch on ignition switch connector rhat matches that arrangement.
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