1st Thread is a Help me thread

[ropinfool]

This is my first post here, so I thought I should do introductions first. I bought a 1991 D250 last spring and so far it's the best truck I have owned.

I have found that most of the time I can just search on the forum for anything I need to know, but I have come across a problem that I just can't find the answer to. I have had a problem with my odometer not working since I bought the truck, initially it only registered about 1/4 of the mileage it should have a low speeds, but recently it stopped working all together. I pulled the dash and guages to check on the gear (as I have read it is most likely the problem) only to discover that a resistor caught fire and damaged a few of the components on the speedo/odo circuit board.

On to what I am needing help with (to the best of my knowledge,) I am looking for pictures or info on what resistors or electrical components were killed, they are really black and I can't tell what they used to be. I hope that the following picture helps to illustrate what I am talking about.

[Mark Nixon]

The top crispy critter was a diode.
The bottom one was a resistor.

That kind of stuff only happens with either high continuous resistance down the line, or a notable voltage spike.
{edit}
Re-reading your post, you mentioned that at one time it was counting the mileage at a slower rate.
It's possible the motor the gear is attached to shorted out and took the rest out with it.

Mark.