Author Topic: Testing voltage limiter on dash  (Read 674 times)

Offline DocMel

  • Full Member
  • ***
  • Posts: 828
Testing voltage limiter on dash
« on: August 27, 2013 - 09:18:07 PM »
My fuel, oil, pressure and water temp gauge quit working on my 71 Cuda.   

From another post its said the cause is most likely the voltage limiter.   I would like to test it before I spend $65 on another one

There are 3 blade type posts on the back of the VL:   

Two posts are connected and go the ignition, so it gets 12 volts there, simple.  I do have a confirmed 12v going in here   

Do I test the VL by checking the output voltage at the third post?  Thats how I am doing it now and it reads 0.15volts.  I thought 5.0v was supposed to be the output

Am I testing the  VL correctly?




Offline MEK-Dangerfield

  • C-C.com Expert
  • ********
  • Posts: 20946
  • I don't get NO respect! Member since 1/25/2002
Re: Testing voltage limiter on dash
« Reply #1 on: August 28, 2013 - 03:50:54 PM »
You probably are testing it correctly, but the 5 volts is pulsed, so depending on your meter, it may not be able to read it correctly.

To be clear, it's the post with the daisy chain wire going to the gauges that should read 5 volts.

Then again, the VL could be dead...

Mike

1970 Challenger - SOLD
2016 SXT+.  1 of 524 SXT+'s in Plumb-crazy for 2016.

Offline dodj

  • Sr. Resident
  • ******
  • Posts: 6197
Re: Testing voltage limiter on dash
« Reply #2 on: August 28, 2013 - 09:52:09 PM »
Remember to connect the -12vdc to the case mounting tab. Connect the +12vdc to the dual spade lug connector. The remaining spade lug connection should swing between 12vdc and zero. The average over time is 5vdc, but your meter will never read 5vdc.
Scott
1973 Challenger  440 4 spd 
2007.5 3500 6.7 Cummins Diesel, Anarchy tuned.
Good friends don't let friends do stupid things. ........alone.

Offline Chryco Psycho

  • Administrator
  • C-C.com Guru
  • *****
  • Posts: 36620
  • 70 Challenger R/T SE 70 tube Chassis Cuda now sold
Re: Testing voltage limiter on dash
« Reply #3 on: August 28, 2013 - 11:01:34 PM »
it is easier to test with an analog meter

Challenger - You`ll wish You Hadn`t