Hi the tacho runs off the alternator & when it stops working it is normally a sign of a fault with the alternator so firstly i would check that the alternator is working corectly
have a 1994 land rover discovery & dont have owners manual. where i can i get one?
If they have both failed at the same time it sounds like a power supply problem. Check fuses
See the related link.
Haberman's Auto Repair downtown 920-7858 Haberman's Auto Repair downtown 920-7858
It should tell you in your Repair Manual. Don't have one go [http://www.themotorbookstore.com/land-rover-range-rover-manuals.html Here]
You should not bypass the relay. Repair the problem.
You find all of the wiring diagrams in the Land Rover Discover Haynes Service and Repair Manual (my edition is # 3016)
Difficult to work on and lots of garages wouldn't touch mine which is a Rover 75 V6 auto. I got a garage to carry out repair for about
Remove the instrument panel cover. Remove the tachometer retaining screws. Remove the tachometer cable from the back of the tachometer. Reverse the process to install the new tachometer.
you need a tachometer
You replace it. Should be next to the trans case.
unbolt from bellhousing and replace with a new one