help plz s13 tachometer acting weird wont work at all.

[elliascool]

so bought a shell used to be a rb20, the guy said he didnt repin any plugs or change up any wirring, swapped in a dual cam ka, turns on and runs but tried 2 different gauge clusters, ones out of a dual cam ka and ones a jdm kmh one.. neither work, all that you see turn on the cluster is the check engine light that stays on when cars off and no key in ignition... idk whats up with that.. then when i turn key to on position but dont turn on car ,regularly the clusters supposed to be lighting up all the lights... all it does is the check engine light and the main backlight flashes.... even when the cars on, only thing different when the cars on is the check engine light goes away.. never had this happen in any of my other s13's.... the rpm, speedos nothing else works... also just took a mint running tach from my other 240 and tried it in this one and clock lighr is on but when i flip switch for lights no backlight and clock light disappeared.. idk what's going on . Helppppz

[Mikester]

CHeck all the grounds on your main harness. There is one that if not connected, will cause some weird shit- to include things staying ON when the key is turned off.

[elliascool]

I checked all the grounds even cut a hole in carpet for the one under driver seat...

[elliascool]

So i figured it out, it was the white box under the fuse box on the side that sits int he gap when you take off the whole plastic cover peice for the fuse panel under driver side, i swapped it with an extra i had ,all lights turn on n everything.