My '99 Frontier recently developed the exact problems described in the following link: https://nissanforum.com/forum/showth...strument+panel. That is, the odometer jumped to 999,999 miles and the engine temp and fuel gauge moved to maximum and stayed there whenever the key is on. The truck only has 23,000 miles on it and runs fine other than this problem. It is not over-heating.

I removed the instrument cluster as suggested by others and cleaned the contacts, which looked to be in excellent condition. No help. I have found others that have had the same problem on the Forum, but I have not found anyone who has published a solution other than cleaning the contacts.

On the printed circuit, there is a diode, which seemed to check out OK, and a resister or possibly small capacitor which I could read with an ohmeter and "seemed" to be OK. The truck is on an island in the southern Caribbean, and the nearest Nissan shop is far away, IF I could even get the truck there.