Rev counter not working

[reverend]

I'm hoping someone can throw some ideas at me. My rev counter (FZR400RRSP) has never worked, the back light is there but it doesn't register (speedo, indicators are ok). There is a strong possibility that it was wired up incorrectly. At the moment the 3 wires at the back of the counter are brown, black and grey going left to right when you stand in front of the bike.
What pick up points should I be looking to investigate?
All ideas appreciated - Had a sneaky test ride yesterday and it was awesome- I bought it as a non runner 2 years ago! The last couple of weeks have had a lot of hours thrown at it and bar the rev counter and front brake light switch I'm almost there.

[Motorcycle Solutions]

If you look on back of the clocks, where the brown,black,and grey wire is they should have these letters to ensure you sit them right, br / bl / gr.

check this first, plus check for loose wire in connecting block at ecu it will be the grey wire in the block of four.

[reverend]

The 3 wires behind the clock are in the right place and they show continuity with the black and grey wires from the CDI unit (the 6 wire block). I've taken the clock apart as much as I can and there doesn't seem to be anything out of the ordinary - every component I could test was ok.

The original CDI unit (which got smashed) was 3TJ-82305-10, BB7263

The replacement unit is BB7208, 3TJ-00
Could the difference in CDI unit effect the rev counter or do you think its a dodgy clock, everthing else seems to be working fine.

[Evilchicken0]

It sounds like a dodgy clock if you can get hold of a known working one just swap them to see.

[sharpey]

hmmm i may have 1 ill have a rumage and see for ya

[reverend]

Thanks Sharpey but I've got some clocks on the way so fingers crossed that will sort it. I'm off to prep the last two panels now. I broke the hairdryer so its wet 'n dry and Scotchbrite for me! Almost there.......