Head unit install = broken speedometer?

[robkule422]

Alright guys,

I recently installed a new Pioneer head unit in my 1999 ford explorer. Almost 20 minutes after I was done installing it, I was driving around, and my speedometer no longer works.

I don't even want to drive the thing until I can get the speedometer working, because it doesn't register any miles on the odometer either. Has anyone experienced something like this before? What should I do to fix it?

Any help would be greatly appreciated.

Rob

[PaulD]

might want to ask this in the Ford Explorer section. Might have inadvertently blown a fuse or have damaged something OR it just might be a coincidence in the timing - it is a 12 year old vehicle.

Did you run any of your own power leads to the fuse block, or was this a simple case of "plug and play" via harness(es)? If you used only the harness, and didn't run anything to the fuse block (or tap into any other circuit), I would agree with Paul that there's a good chance this is a coincidence.

However, if you did run your own power lead, or tap into an existing circuit, either via inline tap-in or fuse block tap-in, you may have inadvertently shorted that circuit.

One way to verify is to first check that all fuses are in working order, then remove the power leads from the radio and see if the speedo comes back. If so, you know where to begin.

There's also a chance you pulled a wire from a harness without realizing it during the under dash installation process. Tinker around under there and jiggle the harnesses and see if the speedo lights up.