confused now

[txbronc82]

ok, so now i'm just all sorts of confused :blink: ,i have followed 2 or 3 different (yet all saying the same thing) diagrams of wiring in a instrument cluster with tach into my 82 bronco. since the first install, everything has worked except the tach, so i thought maybe the tach was bad. well yesterday while my roomie was working on his truck (a cheby) we decided to hook my tack up to his engine. plugging in (at first) only the wire that runs the tach (the wire to the neg side of the coil was unhooked), and making sure there was power to the tach from the fuse box, we both turned our trucks on --- lo and behold, my tach worked :wacko: , and with accurate readings (testing it against his tach when we hooked it up) --- so now im just confused on mine. the whole instrument cluster works aside from the tach. it's hooked up how every diagram and people have told me, using wires #11 and #12 and the neg side of the coil and the wire from the control module, etc etc ...but the tach in the bronc wont read /emoticons/[email protected] 2x" width="20" height="20" /> .....any ideas? anything...no matter how small will help...i have had my moments of idiocy, i'm not above being humbled .. thanks >-

 

[Seabronc]

Did you use the diagream from the EVTM? Your stock harness should have all the wires included and no wiring should be necessary. Just make sure fuse 18 is good or the tac will not work. If all that is good, you need to do some continuity checks of the lines from end to end to make sure you don't have a broken line. ie. check from the attachment bolt on the tac to the various locations.

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