Circuit Board Continuity

[dart14]

1969 coronet convertible 318 auto / standard original dash. I have removed the instrument cluster. When checking continuity on the circuit board, I get a continuity reading on any pin when checked at any light bulb connection or at the fuel gauge or temp gauge. Readings at the pin to gauges vary from 0 to approx 68 ohms, depending on the pin. Is it normal to get continuity from any pin to any connection (ie. hi beam indicator pin to temp gauge) ?
The reason the cluster is out is because the fuel gauge is not working. Good ground at fuel sender. Approx 60 ohms from sender with 4 gals in the tank. Sender was removed and checked and cylce was from approx 10 to 75 ohms. When grounding the sender wire to chassis, gauge did not move. 3 AA battery test on the gauge once cluster removed - gauge moved to 7/8 full so the gauge is good. Sender wire to harness connection at kick panel showed continuity. harness Connection to circuit board pin showed continuity so wiring is good.
Since temp gauge works OK, assume it is not the Dash voltage regulator - would like to pick a new solid state regulator at Carlisle coming up while the cluster is out to prevent future issues.
Not sure where to go next

 

[AR67GTX]

Wish I could help you but I vaguely remember there seemed to be a trick to checking out the circuit board continuity as you described - but I can’t remember it clearly. Seems like you had to be careful of which side of the bulb socket connection that I checked back to the pin, as the other side was common ground. But that may be all wrong.

At least I’ll bump you up to the top. If you have the time I would order an instrument voltage regulator from RTE in Fayetteville AR. Their IVR is superior to the others and has more protection built in.

RTE limiter - rte

 

[BeepBeepRR]

The only things you should have continuity through are the ground paths. Take out all bulbs and check all pins to the end of each path. The voltage limiter Gets 12 volts in and 5ish volts to the fuel gauge and temp gauge.

 

[dart14]

beepbeeprr - great picture
Different results with removing the bulbs

Each pin only has continuity for its respective light except for-
temp gauge
ground (gauge feed on the wiring diagram)
gas gauge
Temp gauge, ground and Gas gauge have continuity with everything

removing the voltage reg -
gas gauge pin has continuity with VR (left slot), gas gauge, and temp gauge
ground pin has continuity with oil gauge and VR (center slot)
temp gauge pin has continuity with temp gauge, fuel gauge, and VR (left slot)

Is this how things should check out ?

 

[BeepBeepRR]

Checking each side of each light to the same pin it traces back to should result in continuity from pin to connector side of each light.
The ground pin and all grounds are tied together so you should only have continuity from the ground pin to any point in the ground path.
One side of the VL is 12v from the pin the other side is 5v which feeds the temp gauge as well as the fuel gauge they are on the same path.

So the VL has 3 prongs one is ground one is 12v in and the other is 5 volts out.
Its a Voltage limiter not a regulator. But to each his own. Hope this makes sense. That picture came from this site in another thread.

This board you can see the paths for each pin. You can use it to trace out your pin paths.

 

[YoungGun87]

The only things you should have continuity through are the ground paths. Take out all bulbs and check all pins to the end of each path. The voltage limiter Gets 12 volts in and 5ish volts to the fuel gauge and temp gauge.
View attachment 1689301

I'm a little late to the party but I'm assuming I can bench test with 4 aa batteries taped in series like that E body bench test vid to check lights by just attaching the ground pin to neg and then going around each one checking and should be fine? I believe 4 aa's come out to 5v output.

 

[BeepBeepRR]

Yes you find the pin and find the end of the line and check them.

 

[451Mopar]

When I converted the IVR to a 5 volt liner regulator, These are some of the calibrations I used:
51 Ohms at the Low mark
20 Ohms at Mid Range (1/2 tank, 180 degrees, 40 PSI oil)
9.79 Ohm at High mark (Full tank, 80 PSI Oil, Temp ??) 10 Ohm in parallel with a 470 Ohm resistor

It takes about 62mAmp to see the gauge move, and full scale at about 150mAmps.

 

[Bird 426]

I would like to know when everything gets working, if your fuel gauge works as expected, or is it lazy when ignition switch is turned on. My Dart was always lazy with the solid state IVR. Someone mentioned going back to the old factory IVR, problem solved. Fuel gauge goes right to tank fuel level when ignition switch is turned on. I have already been chastised for doing this, saying that I will burn my car down, and die an ugly death.
Just putting this out there.
Good luck with your problem!