I'm used to mechanical speedos so i have no idea what to look for.
dashlight doing weird stuff. sometimes speedo fully lit and other gauges and heat/AC controls are dark. somtimes speedo half lit and some or all of the other stuff is lit. heat/AC controls almost never lit. also only the lowest and highest fan settings work for heat/AC.

Any help?

 

For the fan start by changing the speed resistor. It's a 4-wire flat connector under the hood on the passenger side in the big black box.

All of the dash illumination lights are connected together. So if they are changing brightnesses then I would suspect the bulb connections themselves. You'll probably have to remove the cluster and clean the contacts at each bulb in the back.

 

Anyone?

 

There is one sensor on the transmission and one on the rear axle. The one you most likely want is the sensor on the transmission. Ask your parts house for a VSS for the speedometer, the one you want has the drive spline that you will remove the current gear from your old one and install on the new one. One bolt holds it on the transmission. Get the new one first so you can match it up to the one on the transmission.

The one on the rear axle is for the RWAL or 4 wheel ABS system.

 

If this sensor is bad, could it be the cause of my ABS light coming on?

 

Possibly.