help ID a fuse in a 66 mustang

Hello,
I have a 66 mustang convertible....pretty much stock...with ac.....289 v8

I was hoping you could help me ID what fuse I need for the "2.5 instal lt." on the pannel? My old fuse (maybe the original?) has labeled 32V on one end and uss aga 2 1/2.
Outside of the 32V, not sure what else I need to id this for replacement.....think they go by different labels now....I know it's a short fuse but I broke the glass getting the old one out. There are a few that would fit in there though....
what should I look for to fill that spot.

These two lights are not functioning...
the center console light (that shines at the feet of the backseat - below the coin box-
and the glove box light.
I got some new bulbs to try out but still does not seem to work. did a test light check on the fuse box and everything worked fine until I got to the 2.5 install lt. which did not light up. Is that the one that regulates those two interior lights mentioned above?

Thanks,
M  

The fuse is available through most any competent Mustang vendor. The fuse is a 1AG-2.5A glass fuse. Note though that the 2.5A fuse is for the instrument cluster on the '65-'66. The interior light fuse is actually a SFE-7.5A fuse. Look in your owners manual to verify what fuse you are replacing and what circuit is powered by what fuse.

Also, be sure all wiring is intact and plugged in. Here's a nice diagram you can use to locate connectors and trace wire colors back to the headlight switch and fuse box: http://midlife66.com/wiring/66inter1.jpg

HTH...
Mark
.  
Mark Houlahan
Technical Editor for:
-Modified Mustangs & Fords Magazine
-Mustang Monthly Magazine

1965 FFR Roadster 427W/TKO-600 5-speed
1966 Mustang 289-4V/C4 Auto
1968 Mustang 4.6L Three-Valve/5R55S Auto
1990 Mustang 306/AOD
2002 Explorer Sport Trac 4.0L V-6/5R55 Auto

many thanks....I noticed now that the radio is not working either....maybe that fuse was fine and now that I do not have the fuse in; the radio shut off...or I may have blown a fuse.

If I went to pep boys, would they have a 1A-2.5 fuse? or would it be called something different?
thanks,
M  

never mind...I see you have used the new fuse name...so I look for 1AG-2.5  

wrightm:
never mind...I see you have used the new fuse name...so I look for 1AG-2.5

You can also look for a  2 1/2 AGA fuse.(AGA means 1/4 inch D x 5/8 inch H)
Here's a link to a company that has them:
http://www.mouser.com/ProductDetail/Cooper-Bussmann/AGA-2-1-2/?qs=sGAEpiMZZMseCiJT91fwIsB0heZRuSPX678YE10CwFE%3d  

So AS/AGA is the size? Sounds right....I went to Kragen to find the AGA 2.5 and they did not have it. They had an assortment pack of AGA fuses which looked to be the right size; but there was no 2.5...only 1,2,3,4...and so on.
The guy at the store thought I could use a 3.
What do you think?
Do I need exactly a 2.5 or could I go a little bit up or down? I guess I don't really have a firm grasp on the whole fuse situation..

Here is a pic of the only fuse that does not seem to be working. Is this the fuse that is in relation to the radio? What else would this be associated with? The small one in the center....2.5 instlt (btw this is not my fuse box..just the same one I found on the internet.

It was odd though....I checked all of the fuses with a test light; and this was the only one that did not light up (maybe I was not testing properly, but all the rest did light up). So I assumed it was out. The radio had been working just fine though.
I took it out to replace (still waiting to replace) but the radio now does not work.
So i am assuming that this fuse does relate to the radio..but if so, it was kind of strange the the test light did not come on.

 

~~~~~~

 

Thanks so much for that last chart....very helpful to know what goes with what.....
Do you think a 3V would work instead of the 2.5V? I could not find any 1/2 sizes..only 1,2,3,4....

I'm sure I could find 2.5 somewhere but looks like it might be a bit difficult.
What would happen should I put a 2 or 3 in instead?
thanks,
M  

Glass and ceramic tube fuses vary by diameter and length:

• AGU fuses: 13/32” x 11/2”

• ABC, AGC, GBB, MDA, MDL and MDQ fuses: 1/4” x 11/4”

• AGX fuses: 1/4” x 1”

• GBC fuses: 1/4” x 31/32”

• AGW fuses: 1/4” x 7/8"

• AGA fuses: 1/4” x 5/8”

• SFE fuses are 1/4” diameter and change in length as amp ratings increase

• GDA, GDB, GDC, GMA, GMC and GMD fuses: 5 x 20mm


i was looking for the fuse actual SKU numbers...

but all i found so far was this.   very informative fuse catalog..   this is a catalog that every car guy might want to download.. and even print a few pages for the wall....  i posted the critical size info above..

http://www1.cooperbussmann.com/pdf/7e17b38e-88c4-4159-892d-ba9b51f75907.pdf  

for those who don't want to click on the link....


Fuse Selection Criteria

• For electronic/electrical applications, fuse must be rated at 125V or better.

• Voltage must match or exceed the fuse being replaced (125V for
household current; 12V for auto; 24V for heavy duty).

• Fuse must match required fuse characteristic – either fast-acting or
time-delay.

• Amp rating must match that of the original fuse.
A Note on Voltage Rating
All fuses have a voltage rating. To maintain safety, this voltage rating should
not be exceeded in application, although it is acceptable to use a higher
rated fuse in a lower voltage application. For example: A fuse rated for 125
volts is appropriate in household (110V) or automotive (12V), while a fuse
rated for 32 volts is appropriate for automotive (12V), but not for household
(125V). Always replace a fuse with one of the same or higher voltage rating.  

Substituting a 3 ampere fuse for a 2.5 should be fine.  By now, you probably have.  
Bill

1966 coupe
1995 Cobra R

M, one thing I see that hasn't been mentioned is that all the contacts are rusted, and the old fuses are too. On my '66, I removed all the fuses and burnished all the contacts with a small wire brush and got all new fuses. Once it's all shiny in there some of the problems might go away. It even seemed to make my lights brighter.

good luck,  

Hello all....sorry for the length of time before response..I have been overseas for the past 7 months and am again trying to pick up on this problem. So after reviewing my forms and work from before I left, I am trying to go over this again.

First off....that photo of the fuse box, is not my fuse box...just a photo found online of the exact same layout that I have for example. Mine looks quite clean.
So I checked all of the other fuses and they look fine...my problem is the 2.5 inst light fuse in the middle. the small one as seen in the middle.

So I went back to the auto store and found the same problem...they do not have 2.5A fuses...again only 1, 2, 3, 4, 5....

So I picked up a fuse and installed the one that says on it "301 1AG  3A 32V"...it also says equivilent of AGA....So I think I picked the fuse that is exactly the same, except for instead of 2.5A it is a 3A...which everyone I talked to said that it should be fine. Would this be the correct fuse for that spot?

The battery was dead...I charged it overnight and it is still weak (am still charging) but the windshield wipers work and the light under the dash work for sure...too bright out to verify some of the other lights.
I know for sure that the radio is not working (unless battery needs charge even more..will check again).

I used the currency tester on the fuses and found that the light on the tester lit up for all fuses except for the one that I just installed for the Inst. LT....it's a brand new fuse that I assume should work. Any other ideas?

I will continue to charge another night and maybe something might change, but I'm not crossing my fingers. Could it be possible that I still have the wrong fuse? or that I need an exactly 2.5A fuse that I can't seem to find other than online.
From the above post it says the Instrument Panel controls the radio light which I'm guessing also controls the radio and also refers to Inst. Lt on the fuse panel?  

a 3 amp fuse will work..

the instrument lights fuse only has power when the parking or headlights are on.. and the pull out knob is turned to the left.. just short of the click that turns on the dome lights....

its really hard to work on various electrical systems without the minimum of tools...

digital volt meters are 7 bucks to 25 bucks.. a 15 to 20 buck version will last for decades..

you seem to have a continuity tester.. that i am taking is a test light.. with a probe and a light at one end. and gator clip at the other end of the wire.

the power connector on the mustang radio has 2 pins.. a large and a small pin.. the large pin is radio power. the small pin is lighting ..

do you have a proper wiring diagram for you 66 mustang.. if not you can just google.. 66 mustang wiring diagram.. you will find several..


the gauge light wires are blue with a red stripe  

you will probably find that this will help

follow circuit 19 from the headlight switch.. you will see that it goes into the fuse box in this diagram..  then it spreads out around the dash board for the dash illumination..



you will also want to make sure that you have a good dash board ground connection.. or the bulbs won't light up..



this ground circuit must include wires from the engine side of the firewall to the engine..