i recently bought a 2000 Mazda miata. when i bought it the whole dash was taken apart, it needed a new engine wiring harness, and a new ignition harness. i replaced both of them, i made sure to connect everything back up, and made sure everything was in the right spot. i got everything put back together, but when i started it some of the gauges didn't work. the RPM, and the Speedometer don't work, but the temp gauge, and oil pressure gauge works. all the lights turn on, but its just the two gauges that don't work. i have the "ALL DATA" for it, i have tested them both for a resistance with an ohmmeter, i get a resistance of 150 -ish . which is what it says is correct. so i don't believe that its the gauges themselves.