Hey all, back in town for about 10 days before punching out again for a year. Well I'm trying to finish up my 76 so my wife can drive it, but this Haneline 5 in 1 gauge is kicking my butt.

The speedometer behaves like a tachometer. It's electronic, and I've cut the feed wire from the GPS and even all other wires other than power in. But if I fire up the engine, it's a tachometer! I haven't driven it yet, but have 1.6 miles on the odometer.

This gauge doesn't even include a tachometer. Any ideas?

You're picking up ignition noise. If you cut the signal feed for the speedo and left it hanging in the wind, you didn't disconnect it, you turned it into an antenna and its picking up ambient electrical noise. The ignition creates lots of spurious noise on many frequencies, and the input for the speedo is likely picking this up and treating it like an intentional input.

The Haneline kit from BC Broncos has a speedo sender unit in the picture. You mentioned using a GPS module. Did you program the gauge cluster to disconnect the speedo input? Have you tried grounding the speedo input signal to null out the noise?

Is there a .pdf of the instructions?