R33 Nismo Tachno Faulty?

[Komachi]

Hi. Want to get some advices from you guys.

Video here

http://youtu.be/1C9CZL4Thus

I took out the cluster and change LED bulbs and did nothing else. After I put back the cluster this starts happen. I check Power FC which shows the correct 0 rpm. It does it even I took the ecu out and put the key in ignition. I know this appears straight up as a ground issue but where exactly should I check?

Plan A: I know on the back of the cluster "TAM" is the line that goes to the ECU tach output. My plan is the splice that wire and hook a terminal at "TAM" directly but I don't want to do anything potentially stupid yet.

Any help or opinion is appreciated

[Sinista32]

Look through here and see if anything is helpful

http://www.skylinesaustralia.com/forums/topic/144131-how-to-fix-tacho-r33-maybe/