Fuse keeps blowing in the temp, gas guage, tach and shift light circuit

[Jim S]

Why are electrical problems always rooted behing the dash?!!  Any thoughts on why this fuse keeps blowing? I'm thinking about just wireing a whole new set of wires for these four items and bypass the old circuit.  But looking at the wireing diagram it appears it runs through the courtesy light and cigar lighter too.  Any tips are welcome.

[mfg]

1 hour ago, Jim S said:

Why are electrical problems always rooted behing the dash?!!  Any thoughts on why this fuse keeps blowing? I'm thinking about just wireing a whole new set of wires for these four items and bypass the old circuit.  But looking at the wireing diagram it appears it runs through the courtesy light and cigar lighter too.  Any tips are welcome.

To me this sounds like an occasional “ground out” due to a frayed wire… a wire that has been chafing against a piece of metal, and is now occasionally grounding out to it… blowing the fuse.

A real pain in the - - - to find sometimes!

Good luck!

 

[Gunslinger]

Here’s a way to find an electrical short!  🤣

 

[Jim S]

LOL!

[Adam DeRosa]

Check the cigar lighter and make sure the wires are tight on the terminals and not loose and touching each other. I once had a similar problem and discovered it was caused by someone dropping a penny into the cigar lighter receptacle, causing an intermittent short circuit. 

[brad]

Check the shift light where the wire goes into the socket for the bulb. Since the light moves with the shifter, it can break at that point and short out to the case of the light which is ground.

[Jim S]

On 8/16/2025 at 4:46 PM, brad said:

Check the shift light where the wire goes into the socket for the bulb. Since the light moves with the shifter, it can break at that point and short out to the case of the light which is ground.

You nailed it Brad.  The light flickers when I shift.  I put a temporay circuit break where the fuse goes and it trips with movement of the shifter.  That's where it's shorting.