hey guys I have a 1974 plymouth duster. The gauges and the lights for them dont work. I have replaced the gauges and the light but still to no avail. The speedometer works just wondering what you guys thought.

Thanks in advanced duster fanatic

 

Good read here, hope it helps, Check that regulator.
http://www.allpar.com/history/mopar/electrical2.html

 

Here's a list of "stuff" that was ALL wrong on my 67, you need to systematically check it out

The harness connector pins at the PC board were corroded, broken, loose. You can sometimes resolder these. In my case, so many were damaged, I scraped the PC board down to copper, soldered wire pigtails, and made new connectors using "Molex" type connectors from Radio Shack

The voltage limiter for the gauges was bad. One which has enjoyed wide support is this aftermarket one, much improved from original:

http://rt-eng.com/rte/index.php/Main_Page

The SOCKET for the limiter is brass spring fingers in the board. On mine the fingers were NOT contacting the board, and I had to solder short wire jumpers from the brass fingers to the copper board

The gauges make contact with "fake nuts." These work loose get corroded. "Loosen/ tighten" them several times, and better yet, replace the nuts

(One or both gauges themselves may be bad or out of calibration)

Clean the PC board of corrosion. A pencil eraser works on "light" problems. Remember, the high beam, turn indicators, and cluster illumination all has to GROUND on the board.

Examine the removable lamp sockets. Clean the little contact fingers, and "spring" them out a little for better contact, and replace the bulbs

Now you can CHECK the gauges, after you get all of the above checked out for decent calibration. You can "rig" some resistors from Radio Shack to simulate the Chrysler gauge tester box The resistors for the gauges, both temp and fuel are the same:

L = 73.7 Ohms (empty)
M = 23.0 Ohms (1/2)
H = 10.2 Ohms (full)

You would connect one of these resistors from the sender wire to ground, preferably with engine running, I believe the manuals say wait "two minutes" for the gauge to stabilize.

Also remember that in the case of the temp sender, the wire goes through a connection in the bulkhead connector, so this could be loose/ corroded

In the case of the fuel sender, make sure the tank sender is grounded. The factory had a metal clip which jumpered over the top of the rubber connector hose. If this is missing, one way is to clamp a wire around the sender tube with a hose clamp, and ground it to the body.

 

thanks for the info both of you, this will help out lots!!!