I just bought a 1990 240sx hatch with a DOHC swap.
When i bought it the gauge cluster wasn't working, i just assumed that the cluster was bad, but i've swapped it with a known good cluster (both are DOHC clusters), and it still doesn't work.
After looking at it more, some of the lights on the cluster do work, like the door light, brake light, turn indicators, High-Beam, CEL (when ignition is on but engine is still off), you get the picture.
The actual interior illumination lights don't work anywhere, even around the AC switches.
The ecu wiring that goes into the dash has been cut after the harness clip on both sides, but the 5 wires I'm told matter are connected well, with good cont. to the back of the cluster.
Now to the weird(er) stuff.
There wasn't any voltage coming from the ecu on the Tach wire (Yellow/red? [from memory]) So we assumed that the ecu was messed up some how. I swapped out to my friend's ecu out of a car that hasn't been run in a week or so (seized motor), but ran fine before that. (also S13 DOHC) the tach registered a signal, but the car wouldn't run at all. Under full throttle it would rev VERY slowly (read on tach), but die as soon as the throttle was released. I went back to my ecu..

My ECU has a 10 on it in big letters, his had a 28.
Is there something i'm missing? are both ecu's bad with different problems? I'm lost and new to 240's, so help would be great. Thanks