Guage cluster mayhem.

[Ratchet Restos]

Need a gauge cluster guru. (1973 duster slant 6 car)

I bought a duster that had ammeter fire (melted cables and bit of a mess) knowing there was an issue I am having issues with my dash lights and gauges.
1) I popped the cluster apart to clean the speedometer front plastics.(didn't open it any further)
2) checked the blue/white wire in the circular fitting ( it is getting power when key is turned.)
3) light switch works (dome light, headlights, taillights, glove box light or working)
4) the oil psi light works intermittently (will show light every so often but everytime I turn the key.)
5) I checked the sending unit in the fuel tank for ohms and it is showing 37 at roughly half tank at the wire. Guage is not working
6) temperature sensor is new and so is the wire. Guage is not working.
7) I did complete a ammeter bypass so alternator Guage will not work.
8) none of the instrumental panel lights work and bulbs and connectors are brand new. (5/8 and I checked the part where they screw into the board.)
9) car was to far gone to check anything worked when I purchased it.
10) the push in wire that goes into the back of dash is also getting power but won't light.
11) I grounded the column and dash on the corner of the car where the lower dash bolt is. (Bout to just run 1 straight to the battery after reading electric issues on forums.)

11! bonus question.. the speedometer Guage is not at 0. When it was put I noticed it was 10 or so. I used an old cable and put it down at 0 but when you jostle it, it goes back to 10 or so.

Anyone got some advice or other things I can check. Bit of a long question but I want to cover everything I have tried

 

[jos51700]

Pick one Guage, trouble shoot that.

See how many get fixed from you doing that.

 

[67Dart273]

THE FIRST QUESTION IS, "what in the hell are we workin on?"

1928 hemi Farmall tractor?



1943 Supermarine Spitfire?



All everything aside, the year/ make/ model IS important. Also is this a Rally cluster or standard cluster?

 

[Dana67Dart]

I bought a duster

So we know it is not an early A, it's not a Dart, valiant, or barracuda, so that rules out 67 to 69 it must be 70 to 76. But which dash!!!!

 

[67Dart273]

So we know it is not an early A, it's not a Dart, valiant, or barracuda, so that rules out 67 to 69 it must be 70 to 76. But which dash!!!!

Well and the WIRING changed almost every single year, and REALLY changed in 73, and again in 74, AGAIN in 75, AND AGAIN in 76!!!

 

[Ratchet Restos]

THE FIRST QUESTION IS, "what in the hell are we workin on?"

1928 hemi Farmall tractor?



1943 Supermarine Spitfire?



All everything aside, the year/ make/ model IS important. Also is this a Rally cluster or standard cluster?

Totally spaced that. I'll edit and 1973 duster slant 6 car

 

[CFD244]

Oil pressure light, so it's not a Rally

 

[Dana67Dart]

Oil pressure light, so it's not a Rally

Good catch!

 

[67Dart273]

Totally spaced that. I'll edit and 1973 duster slant 6 car

LOLOL OK. Now what you need to do is run over to MyMopar and download the two volumes for the 73 manual. I think it is Dodge, not Plymouth, but most of it is the same. The wiring is quite different for either 72 or 74

I would take some notes and make some tests with the cluster out of the car

1....Even if the ammeter has been bypassed the original ammeter wires may still be "hot." So locate them, the big red and big black, the only two at the cluster with eyelet terminals. Splice them together, even if you use a screw and nut, and tape it off "safe."

Now you can make tests as if the cluster was connected.

For testing the cluster, it MUST be grounded. When installed the mounting screws ground it, and that was poor design. Recommend you find a ground point on the PC board and create a pigtail which you can bolt to the instrument frame/ column support. You can easily trace the circuit by looking at the board. All the illumination lighting grounds to one point

To see if you have dash light power, determine if lighting outside the cluster works---shift quadrant, radio, heater controls. If so, find and check the orange wire going to the cluster. It should come on with park or head, and with the switch knob rotated "left"

For testing the gauges, there are a number of potential problems

1.....Sometimes the PC board connector pins get loose, they were originally "crimped." There is some old thread(s) on here about repair. You can solder the pins
2.....The instrument regulator/ limiter may be bad, or the contact fingers in the board may not be making contact with the traces. Solder jumpers across from the board traces to the finger contacts
3...The stud nuts on the gauge studs may not be making contact, or corroded. Loosen/ tighten them a few times to "scrub" the board traces and tighten them
4...Of course it's possible that something, short, etc, happened to burn up the gauges. Later you can test them.
5....Your really need resistors to properly check gauges for calibration, but for a quick check, power up the board to the IGN pin and ground, and ground the sender terminals. Either gauge should jump fairly quickly to the right "peg."

 

[67Dart273]

10) the push in wire that goes into the back of dash is also getting power but won't light.

Can you explain, I don't know what you are referring to

 

[67Dart273]

11! bonus question.. the speedometer Guage is not at 0. When it was put I noticed it was 10 or so. I used an old cable and put it down at 0 but when you jostle it, it goes back to 10 or so.

If you unhook the cable, and actually it should not matter, and it's not zeroed, that's a mechanical problem with / in the speedo.

 

[Ratchet Restos]

10) the push in wire that goes into the back of dash is also getting power but won't light.

Can you explain, I don't know what you are referring to

The push in light socket that has 2 wires coming from it. I can get a picture today.

View attachment 1715883805

11! bonus question.. the speedometer Guage is not at 0. When it was put I noticed it was 10 or so. I used an old cable and put it down at 0 but when you jostle it, it goes back to 10 or so.

If you unhook the cable, and actually it should not matter, and it's not zeroed, that's a mechanical problem with / in the speedo.

So I'm guessing I'll have to remove the gauges again.

 

[Ratchet Restos]

LOLOL OK. Now what you need to do is run over to MyMopar and download the two volumes for the 73 manual. I think it is Dodge, not Plymouth, but most of it is the same. The wiring is quite different for either 72 or 74

I would take some notes and make some tests with the cluster out of the car

1....Even if the ammeter has been bypassed the original ammeter wires may still be "hot." So locate them, the big red and big black, the only two at the cluster with eyelet terminals. Splice them together, even if you use a screw and nut, and tape it off "safe."

Now you can make tests as if the cluster was connected.

For testing the cluster, it MUST be grounded. When installed the mounting screws ground it, and that was poor design. Recommend you find a ground point on the PC board and create a pigtail which you can bolt to the instrument frame/ column support. You can easily trace the circuit by looking at the board. All the illumination lighting grounds to one point

To see if you have dash light power, determine if lighting outside the cluster works---shift quadrant, radio, heater controls. If so, find and check the orange wire going to the cluster. It should come on with park or head, and with the switch knob rotated "left"

For testing the gauges, there are a number of potential problems

1.....Sometimes the PC board connector pins get loose, they were originally "crimped." There is some old thread(s) on here about repair. You can solder the pins
2.....The instrument regulator/ limiter may be bad, or the contact fingers in the board may not be making contact with the traces. Solder jumpers across from the board traces to the finger contacts
3...The stud nuts on the gauge studs may not be making contact, or corroded. Loosen/ tighten them a few times to "scrub" the board traces and tighten them
4...Of course it's possible that something, short, etc, happened to burn up the gauges. Later you can test them.
5....Your really need resistors to properly check gauges for calibration, but for a quick check, power up the board to the IGN pin and ground, and ground the sender terminals. Either gauge should jump fairly quickly to the right "peg."

I will be attempting these fixes. Also it being a ground would probably be a good start considering the oil light works randomly and with the plastic being so old I'm afraid to crank it down tight.

 

[hotrod swinger]

The push in light socket that has 2 wires coming from it. I can get a picture today

I think that is the seatbelt warning lamp.