Fuel and temp gauge

[Garys1969RR]

I am trying to get the fuel and temp gauges to work on a 69 RR that I just bought. The charge indicator wires were moved to an aftermarket amp gauge, would this affect the instruments? I already put in a good working voltage limiter. The turn signal indicator and brake indicator lites work, so I know there is power to the instrument cluster. How do I check the gauges?

 

[440roadrunner]

The ammeter is wired completely separate and would have nothing to do with your problem. If the ammeter wires are disconnected, you will have NO power in the car, no headlights, no dome, no ignition, etc


Can you post (find one) a photo of the rear of the cluster? Here's how "this" works.........

There is switched 12V "run" ignition feeding to the cluster. This supplies power to the gauges, brake warning lamp, oil warning lamp, etc

This power goes to a plug-in "voltage limiter" that is a small rectangular box plugs into the PC board. It "used to" work similar to a flasher unit, IE switches on / off, and provides pulsing power to the guages "about the same as" 5V DC

This power comes out of the IVR and goes via the circuit board traces to the two gauges. The sender end of the guages go via PC board traces back to the harness connector

GENERALLY what goes wrong with these girls:

1...The PC board connector pins are riveted, and get loose, Either solder / repair them or buy repop boards

2...On my dart, the spring fingers for the IVR socket were not making contact with the board. I had to solder jumpers across between the fingers and th eboard traces

3...VERY likely the IVR is bad. I bought mine at "RTE" Real Time Engineering It's a solid state replacement

4...The gauge stud nuts can be loose / corroded. Good idea to replace the stamped fake nuts with real ones, and loosen / tighten them a few times to scrub corrosion off.

5..Other than that wiring connections in the bulkhead connecter (temp) the kick panel connector (fuel) and the wire end connectors, and of course the senders themselves.

"Quick check is to remove the sender wire, ground it and turn the key to run. Gauge should immediately head towards hot / full

If you do not have one GET yourself a factory Chrysler manual. You can download many years FREE over at MyMopar, as well as somewhat simplified wiring diagrams

http://www.mymopar.com/index.php?pid=31

 

[bigmanjbmopar]

The cluster has to have a good ground it uses the screws that mounts it as a ground reference. Make sure you have a good ground first.

 

[Garys1969RR]

Yes I've grounded the wire from both sending units with no response at gauges. Guess I will pull the cluster out and see what I can find.

 

[440roadrunner]

Before you pull it out, you should be able to unplug the IVR with the cluster in place. It is probably the most likely failure, and it it's not a solid state replacement, I would just get one and try it first.

Bear in mind, I do NOT usually advocate "throwing parts" at a problem.

 

[bigmanjbmopar]

Key was on right? and you said you have replace the limiter already? Check the circuit board for blown traces mine was like that had to temp fix it with a solder bridge until new electronic board showed up. Also check the pins they will come lose. If the amp meter was disconnected that usually means something blew out at one time. Make sure your fuses are all good.

 

[Garys1969RR]

Yes key was on, turn indicators work. Brake lite works. Limiter was taken from my other RR where the gauges work. And they still work after swapping limiters. Is there a gauge circuit from the fuse box? Fuse for instruments?

- - - Updated - - -

It has an after market amp meter installed which works. Any one have an old instrument cluster I can experiment with? That wont cost too much? Even my speedo works. Thanks

 

[440roadrunner]

Consult the factory manual. I keep trynna tell you guys, you can download them FREE from MyMopar And no "I don't work there."

Power for that circuit is NOT fused, it comes direct from the ignition switch "run" line (IGN 1)

I didn't catch that you had swapped limiters

Problems in no particular order:

As above, broken /loose PC harness connector pins.

Problems with the harness connector

On my car the spring fingers where the IVR plugs in were not making contact I had to solder jumpers across to the PC board.

I realize that neither gauge works, but could be bad connections at the nuts on the gauge studs

The gauges could both be bad, damaged (ruined) by a previous bad IVR

A crop out of the diagrams:

Look at the switch where it says J2-16DBL (IGN 1) this is the dark blue ignition "run"

The wire below comes off that same terminal is G5-18DBL that wire goes directly to the PC harness connector

Look at the cluster connector, find the wire at bottom left, "Voltage limiter, etc" is G5-18DBL. That wire, that pin, supplies switched ignition to the IVR and warning lamps.

IF THE brake and oil warning lamps work, that circuit is getting power. Check the PC board for damage, check the IVR contact fingers for good contact, and the gauge nut studs

 

[Garys1969RR]

It looks as though the brake warning light (which works) is fed current through the same dark blue wire that also feeds the voltage limiter. So I am assuming the circuit board has power to the IVR. I will pull the cluster and check all the connections for good contact.

- - - Updated - - -

I have looked at the wiring diagrams, and they are helpful.

 

[440roadrunner]

So I am assuming the circuit board has power to the IVR. I will pull the cluster and check all the connections for good contact..

As I mentioned earlier, suspect a bad connection between the PC traces and the IVR socket fingers.

 

[bigmanjbmopar]

If you're going to pull it out, you might want to check out the newer electronic circuit boards with the limiter built in the prices have come down for them and the investment is worth every penny. If not and you have loose or broken connections you can hack it up with solder and stuff like the picture above.

 

[Garys1969RR]

I found another 69 Satellite inst cluster for $40. Checked it all out today and was able to get the gauges to respond (after some cleaning of the PC board and gauge nuts/mounts.) I pulled the IVR that was in my RR, and it works good. The volt meter pulsed back and forth when hooked to the gauge power feed line. It's Interesting how Chrysler grounds the other connection on the gauge through the sending unit to get the gauge to operate. So when I ground the sending unit wire, that completes the circuit and the gauge moves!

 

[Garys1969RR]

So now that I have a pretty good idea as to how the instrument cluster/gauges operate, I will pull the instr cluster out of the car and see why the fuel and temp gauges wont respond when I ground the sending unit wire. Plus I have 2 gauges that I know work OK.

 

[Garys1969RR]

Put the other instr cluster in today, and got the fuel and temp gauges to work. Looks as if the old cluster had a loose/faulty connection where the voltage limiter plugs in to the PC board. Thanks everyone for your help!

 

[munger77]

I'm doing about the same thing. I just cleaned up my circuit board traces with a pencil eraser, chased wires to the cluster ensuring continuity, installed the IVR voltage limiter on the back of the cluster (made sure it works too), painted my dash needles bright orange which made a huge difference in looks, and replaced the gauge nuts with "real" nuts for a better connection. So tomorrow may be test day for my gas and temp gauges. Hope they work; Fingers are crossed...