!973 Challenger. Rallye gauges. I used two D batteries and alligator clips to test all the individual gauges. All gauges moved to the center. I believe all the gauges to be good. The voltage regulator is new. Just recently i found the 3 way wire that jumps to the other gauges. ( the wire that daisy chains them together). With everything plugged in i still have no gauges. What am i missing here ? Thank you for the help !

My 73 had ground issues. I had to add a jumper to get a better ground.

Check your voltage at the limiter even if it's new it could be bad.

Make sure it’s screwed to the dash frame. That is how it’s grounded.

Is the ground reinforcement wire in tact?

I don’t recall a ground strap or wire . ? Could you explain where the ground goes to and from ? What should be hot on the voltage reg ? Thanks .

Like he said, the dash frame is supposed to be the ground. In my case I couldn't get a good ground no matter how much I cleaned and tightened it so I added a wire from the metal gauge cluster to the ground wire under the steering column. that grounds the dash to the column.

If the E body is like the 71 B body, the gauge mounting is kind of hap hazard, so the factory added a ground strap from the panel to the left metal frame work of the body. It shows it in the service manual.

Strap? Is a regular wire the harness got to attach to a J nut with a screw to dashframe. The other end of the wire plugs straight to a VL bracket provision on rallye cluster and is on the multipin conector on standard clusters. On B bodies at least.

BE CAREFULL... if the VL is NOT grounded you can BURN the gauges. The VL requires - and + to work. If - is missed the points inside will keep closed allowing 12 volts to the gauges. The ground wire must be in place. The chassis ground to cluster is also good to be there and nice..

on pic the VL with the bracket provision for the ground plug. The wire gets a wider terminal ( prong is also wider ) to save from connect a diff wire there which is not the propper ground wire

Thanks for the replies. I am about to go to the garage and dig into it. I will report back .

I removed the wires to see the VL. The light blue wire coming from the VL makes a connection to two gauges . Do I have to add a jumper wire to have all three connected ? Thanks

Edit . A connection between the light blue /gray on the oil gauge and the empty dark blue/ post . On the gas gauge .

Like this ?

Yes. Normally the wire feeding between gauges and VL is black. Dunno wher it comes that one.

FYI

New VL harness

.....

Thanks for the help ! I`m gonna order the new harness and I will report back . One other thing. Using a test light on the gauges the light pulses like a turn signal. Does that show the VL is working? Thanks again !

Yes that's the way it limits the voltage.

The problem is the jumper should have 4 connections on it not 3. You can see it in the picture on ebay link of back of gauge and on the wire diagram. The 1 you have might be from a standard dash.

UPDATE: Installed new VL harness to oil gas and temp. Went to hook up ammeter. Red connected . As soon as I touched black it turned red hot in my fingers . No damage anywhere but woah. So I reconnected the leads for the ammeter back together . This is how it has been wired for last 20 years. Besides the ammeter leads being connected everything is wired as it should . Starting with oil gauge . Using a test light both posts will pulse like a turn signal.The wire on the oil pressure sensor is also pulsing. Prior to the new harness oil wire was dead. So i thought i had a good gauge , its wired correctly. I have hot at the oil sensor . Why no gauge ? Bad sensor? P.S I`m just highlighting oil gauge because i feel easiest to get working . Thanks for all the help . If you have advice please explain it to me in the simplest terms. Like i`m 5 . 😂

Is being a bit hard to read you.

yes you can get sender damaged... or gray wire.

about ammeter. after 50 years of use and abuse there is a chance the ammeter isolators are gone now... they could be already cracked quite ago but with the movement it could miss a piece and is being grounded. Time to remove the assembly and replace the isolators. It would be even better reinforce the ammeter studs to the shunt inside

https://premiumdashdecals.com/shop/dodge/dart/dart-demon/all-car-lines-ammeter-insulator/

some reading about how an ammeter is inside here:

https://www.forbbodiesonly.com/moparforum/threads/dissection-and-study-of-a-mopar-ammeter.199179/

Yes the rectangle isolator piece is missing . What material could I use in its place ? What size nuts / thread go on the ammeter post ? I’m gonna retest the gauges and make sure they are good. Would the red wire touching the back of gauge cluster without the isolator cause a short or potential melt down ? Thanks .

Yes you need to isolate the studs on the ammeter, otherwise it's meltdown/fire time, you could use some electrical insulated fiber washers, they need to be under the nuts that will tighten the ammeter studs to the housing, I'd recommend you buy/purchase a test meter, not a test light, to check for continuity/ground after you install the insulated washers under the ammeter retaining nuts, then ground one lead of the test meter to the cluster main housing and test each of the ammeter studs with the other lead while maintaining ground with the first/black lead of the meter, make sure the meter is on continuity/Omega, depending on the type of meter you have: digital or analog, it may also have an audible sound/buzz for ground/continuity, needle movement or digital display? whatever it is, you DON'T want any ground or continuity when probing the ammeter studs individually while maintaining ground with the black lead on the main cluster, if you have ground/continuity then either you didn't properly isolate the studs, the gauge may be defective, or a host of other maladies we can guess at all day, you really need a good meter to help you find/solve issues.... FYI: depending on your meter the only continuity you want to see on the ammeter studs is when you apply both test probes to each stud at the same time....AFTER you've confirmed each stud is isolated from the cluster housing/chassis ground

As far as the oil gauge function, make sure you have the correct sending unit it should look like this....



Mike