• Welcome to For E Bodies Only !

    We are a community of Plymouth Cuda and Dodge Challenger owners. Join now! Its Free!

How do I test my rally gauges

hsb shadow

Well-Known Member
Joined
Dec 30, 2022
Messages
78
Reaction score
47
Location
43040
I'm going to start going through my rally dash in the next couple of weeks and I was wondering if anybody had a write up for testing. I bought a rebuilt gauge set for my other cuda but some of the work inside was just terrible and had to be redone. The current car probably hasn't been on the road in over 30 years so I'm not sure the status of all the gauges. Thanks in advance
 

Sinitro

Active Member
Joined
Mar 19, 2021
Messages
32
Reaction score
8
Location
Southern California
Basically the oil, temp and fuel gauges are a 5V dc gauge. Using some AA cells wired in series across each gauge, it should read about 70% scale. If no reading then bad gauge..

Just my $0.02...
 

Xcudame

Well-Known Member
Joined
May 27, 2023
Messages
891
Reaction score
647
Location
Southeast Arizona
If you haven't already, you'd be wise to purchase a $60 electronic voltage regulator from Real Time Engineering. The OEM regulator shorts out and drops 12 volts dc to the 5 volts dc gauges making them non-functional.
RTE limiter - rte
 

hsb shadow

Well-Known Member
Joined
Dec 30, 2022
Messages
78
Reaction score
47
Location
43040
Thanks for the info. I just pulled the dash and hope to be looking at the cluster over the next two weeks. From my reading so far you can check three of the four gauges by putting five volts across it but you're supposed to do something different with the amp gauge or you'll blow it out is that correct
 

Sinitro

Active Member
Joined
Mar 19, 2021
Messages
32
Reaction score
8
Location
Southern California
If you haven't already, you'd be wise to purchase a $60 electronic voltage regulator from Real Time Engineering. The OEM regulator shorts out and drops 12 volts dc to the 5 volts dc gauges making them non-functional.
RTE limiter - rte
The RTE limiter is an awesome product but..
The 1 thing I dislike about the RTE limiter is that the Mopar OE dash gauges have a built-in thermal system that needs to warm up, and with the RTE's lower voltage output this takes a few minutes. Note that the OE voltage limiter applies a higher voltage just for an instant, which warms up the gauges faster when the ignition switch is turned ON so they are more accurate faster. My experience is with the RTE limiter the gauges will read about 25% lower until they warm up, this can take a few minutes. My recommendation to RTE would be to redesign using an inexpensive, smart processor that applies a higher voltage just for an instant upon ignition turn ON, and this will heat up the gauges thermal system faster...

Just my $0.02...:thumbsup:
 

Sinitro

Active Member
Joined
Mar 19, 2021
Messages
32
Reaction score
8
Location
Southern California
Thanks for the info. I just pulled the dash and hope to be looking at the cluster over the next two weeks. From my reading so far you can check three of the four gauges by putting five volts across it but you're supposed to do something different with the amp gauge or you'll blow it out is that correct
Correcto..
By applying a low DC voltage across the gauge's contacts, it should read something.. If nothing then the gauge is bad..
This applies to the gas , water temp an oil pressure gauges not the amp..

Just my $0.02... :thumbsup:
 
Last edited:

moparleo

Well-Known Member
Joined
Oct 17, 2011
Messages
6,922
Reaction score
1,701
Location
So. Cal. Riverside area Moreno Valley
It doesn't hurt to let the car /oil/coolant to warm up anyway. It takes longer for those to warm up than your gauges.
These are 50 year old cars people. Things took longer back then when people had more patience.
 
Back
Top