2000 GT - CAR WON’T START

I was changing my one of my fuses because it was blown, when I was done I went to try and start my car up. It was just crank and not start. So I left the key in the ignition with it just turned to the on position. The theft light flashes over and over with dashes on the odometer reading (———————). The car started before, this is the first issue. I know the previous put a SIMCO dash in from another junkyard GT. It started fine with no issues then, why is it causing some now?

wmburns said:

The cluster displaying all dashes likely means there's a power problem (especially after a blown fuse).

Confirm key on power in and out of fuse F2.34, F2,2, and F2.8.

What to do next depends upon the test results.

1999-2004 MY fuse panel schedule:
https://www.allfordmustangs.com/for...r-swap-wont-fire-please-help.html#post2669271

1996+ Crank with no start check list
https://www.allfordmustangs.com/forums/4-6l-tech/336452-1997-mustang-wont-ignite.html#2984838

In the crank with no start list pay special attention to the part about the checking the CCRM/PCM ground that goes around the battery to the radiator core support.

Click to expand...

wmburns said:

The cluster displaying all dashes likely means there's a power problem (especially after a blown fuse).

Confirm key on power in and out of fuse F2.34, F2,2, and F2.8.

What to do next depends upon the test results.

1999-2004 MY fuse panel schedule:
https://www.allfordmustangs.com/for...r-swap-wont-fire-please-help.html#post2669271

1996+ Crank with no start check list
https://www.allfordmustangs.com/forums/4-6l-tech/336452-1997-mustang-wont-ignite.html#2984838

In the crank with no start list pay special attention to the part about the checking the CCRM/PCM ground that goes around the battery to the radiator core support.

Click to expand...

wmburns said:

The cluster displaying all dashes likely means there's a power problem (especially after a blown fuse).

Confirm key on power in and out of fuse F2.34, F2,2, and F2.8.

What to do next depends upon the test results.

1999-2004 MY fuse panel schedule:
https://www.allfordmustangs.com/for...r-swap-wont-fire-please-help.html#post2669271

1996+ Crank with no start check list
https://www.allfordmustangs.com/forums/4-6l-tech/336452-1997-mustang-wont-ignite.html#2984838

In the crank with no start list pay special attention to the part about the checking the CCRM/PCM ground that goes around the battery to the radiator core support.

Click to expand...

I am mechanically inclined, but when it comes to electronics that goes right over my head. I just need to know if I need my gauge cluster reprogrammed to my ECU because that isn’t the the original cluster that came in the car. It was a cluster out of a junkyard GT. The car still won’t start, it will just turn over. It is still displaying all dashes in the odometer and the theft light still blinks rapidly.