keep blowing fuse #8

[NCtrueconservative]

Hadn't been on in a while. Last time I drove the car (73 rallye challenger), I kept blowing fuse number 8 (one in the lowest right corner on the fuse block). At first it seemed to blow when I floored it, and I would lose my tach, signal lights, etc.  But then, it got to where as soon as I put a new one in, and started the car, it would blow.  I crawled under the dash and couldn't see any open wires that could be shorting out or anything. Any ideas??

[Jamiez]

When mine was blowing it was the wire from the transmission for the reverse light grounding against the brake booster.

Unfortunately fuse 8 runs a lot of small bits which go hot with the key (radio, turn signals, reverse light, clock, etc) so it will probably be a real pain to track down

[TinCuda]

I am having the same problem.   I replaced my turn signal flasher thinking it might be blowing the fuse due to some resistance or something.   No help.

Replacing my fuse will fix my signal problem for a short time.   Everything works fine, start the car, drive it around the block and by the time I get home, the fuse is blown again.

No loose wires under the dash and no radio installed.


 
 

[moparmaniac59]

Mine just blew this past weekend. I haven't had a chance to really dig in. I did check turn signal wires & they looked good from the bulb sockets. Guess I've got some more digging to do! 



                                                                               Matt B.

[ShelbyDogg]

Put a bulb across the fuse terminals. The light will come on bright if the short is there, Start unplugging sections of harness till the bulb goes out, then start following those wires till you find the short.  On my 70, the lower right fuse goes to my running lights, dash lights and cig lighter.

[moparmaniac59]

According to a '74 service manual, cavity # 8 supplies the: Backup Lamps, Turn Signal Circuit, Radio, Reverse Gear Indicator lamp. It should be the same for '73. 



                                                                           Matt B.

[ChallengerHK]

According to a '74 service manual, cavity # 8 supplies the: Backup Lamps, Turn Signal Circuit, Radio, Reverse Gear Indicator lamp. It should be the same for '73. 
                                                  Matt B.

Of that list, I'd be looking at the hot lead for the radio first to see if it's shorting.