• Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Gauges

  • Thread starter Thread starter suki243
  • Start date Start date Feb 15, 2007
S

suki243

Member
Dec 19, 2006
662
0
19
Southern California
Feb 15, 2007
#1
  • Feb 15, 2007
  • #1
Hey guys, I was wondering, what is the procedure on testing whether the gauges are broken or the sensor is no longer working?
Right now my fuel, speedometer ( is a little off), after market oil pressure gauge, and aftermarket RPM gauge are the only ones that are working.
The amp current one just stays in the middle all the time even when the ignition is off, the water heat one stays below 0, and the oil heat one stays at 0 all the time.

I have a multimeter if that helps.
 
T

toolwench

New Member
Jan 4, 2007
21
0
0
Los Angeles area
Feb 16, 2007
#2
  • Feb 16, 2007
  • #2
I can't say I know for sure what to check other than the wires themselves. When my coolant temperature gauge started reading only zero, I was ready to check the gauge and the sensor separately, but it turned out that the wire had snapped at the sensor. Therefore, I put a new connector on, hooked it up and it worked, so I didn't need to check my gauge or my sensor.

When I first got the car, my alternator gauge only moved about a hair's width except when I started the car, it moved about three hair's width. After replacing the alternator wiring loom during an engine swap, my gauge now moves, but only enough that I know it's working. I don't really need more than that.

If I were you, I'd trace the wires and verify that they're all hooked up correctly. Beyond that, I'd bust out my service manuals.
 
S

suki243

Member
Dec 19, 2006
662
0
19
Southern California
Feb 16, 2007
#3
  • Feb 16, 2007
  • #3
Mine don't move at all they're fixed there, I tried to locate the connectors and from what I can tell they wires are fine.
 

geostang351

Member
Mar 30, 2005
946
0
17
Danb., CT
Feb 17, 2007
#4
  • Feb 17, 2007
  • #4
suki243 said:
Hey guys, I was wondering, what is the procedure on testing whether the gauges are broken or the sensor is no longer working?
Right now my fuel, speedometer ( is a little off), after market oil pressure gauge, and aftermarket RPM gauge are the only ones that are working.
The amp current one just stays in the middle all the time even when the ignition is off, the water heat one stays below 0, and the oil heat one stays at 0 all the time.

I have a multimeter if that helps.
Click to expand...

This is my take on the situation; The speedometer works because it is mechanical and has no electric hookup to work or not work. Your gauges that work are aftermarket guages that probabaly require 12 volts that have been hooked up to a 12v source either from the fuse box of direct to battery. The gauges are new as well as the wiring that goes with them (probably) and maybe even the sensors.

The gauges that don't work are the origainal ones. So my GUESS would be that the voltage regulator that is supplying power to the original gauges is bad (a $15 part from your local parts house). THe voltage regulator I believe supplies 8V of power to the gauges. Replace that and see what works.

The voltage regulator is the small brown rectangular device shown on the large gauage on the right and has two wires running to it.

 

Attachments

  • DSC00602.webp
    22.8 KB · Views: 114

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Feb 17, 2007
#5
  • Feb 17, 2007
  • #5
geostang351 said:
.
So my GUESS would be that the voltage regulator that is supplying power to the original gauges is bad (a $15 part from your local parts house). THe voltage regulator I believe supplies 8V of power to the gauges. Replace that and see what works.
Click to expand...
the part is actually about 25-40 bucks and the soldered tabs break of real easy(cheap part). Go to radio shack and make your own.They sell voltage regulators for about 3 bucks and you want one that steps the voltage down to about 5 volts
 
You must log in or register to reply here.

Similar threads

M
1996 GT Speedometer electrical nightmare
  • moon96gt
  • Oct 7, 2026
  • SN95 4.6L Mustang Tech
Replies
2
Views
154
SN95 4.6L Mustang Tech Oct 17, 2026
CAMTWO1070
Electrical Issues with my 2006 mustang gt
  • VerneVdV
  • May 22, 2026
  • 2005 - 2009 Specific Tech
Replies
0
Views
194
2005 - 2009 Specific Tech May 22, 2026
VerneVdV
F
Fox 1990 Mustang GT 5.0 A9L – Engine suddenly shuts off but immediately restarts when key turned
  • FishermansFriend
  • Aug 9, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
16
Views
643
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Aug 30, 2026
General karthief
Engine Random Misfire at idle.
  • Gulftown980x
  • Jul 29, 2026
  • SN95 4.6L Mustang Tech
Replies
11
Views
556
SN95 4.6L Mustang Tech Jul 31, 2026
squeak93
T
Help with a 95 5L crank no start
  • TheBubbaJoe
  • Nov 4, 2025
  • 1994 - 1995 Specific Tech
Replies
3
Views
551
1994 - 1995 Specific Tech Nov 5, 2025
AeroCoupe
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?