VC tach on 420 Help

Drift Widow

New member
Hope someone can help me....I am a noobie here been lurking a while....

Purchased new VC tach...engine 420 ARC adjustable flywheel
Electric Start
Honda 30500-Z5K-801 Coil UT2...I have the wiring as follows:
Orange: Directly to positive on battery
Red and White: To one side of my SPST (accessory) switch other side to positive side of battery
Black: Ground
Green: Is hooked up with yellow (coming from coil) on one of SPST kill switch, other side of switch going to ground.
Yellow: Open capped off not going to nothing.
Note: Black and Red coming from coil is tied together.
Note: After following installation instructions and.....before doing anything after hooking it up I went set up limit held button in turned on accessory switch and it never worked past that point..only...backlight comes on that's it kills my spark when tach is plugged in.........UPDATE: Honda coil did not seem to work out to well...was new...but timing seemed really retarded...did not mess with timing of flywheel just put original coil back on...I believe it's riginal... and tach still does not work


Drift Widow

New member
Now since I have the original coil back on just has one wire running from the of the drawing is the same....tach still doesn't work...

Drift Widow

New member
Yes ....instructions are on their website....hopefully I will get some help from them tomorrow on Monday....there wasn't nobody there that could help me when I called in Friday....Thanks to all on here for trying to help me...I think I just got a bad wasn't taped...looked like it may have been handled ??

Drift Widow

New member
Ok....finally received some help from there technical dept..........
The UT2 coils are not compatible with this tach as the tach reads the pulse signal from the kill wire and the UT2 has an internal timing advance mechanism that does not output an ignition pulse signal.

We haven’t tried an UT2 coil with this tach personally, but I think it’s reasonable to assume that it burned out the tach if it’s not responding to a one-wire coil.


Dawg 89
Saw were the instructions said not compatible with cd ignition .
Some one else got a bad one as well .
No signal pulse should not burn anything up . Its electronic the smoke got out .
Post #1 states tried ut2 coil then switched back too original.