Sam, you wouldn't happen to have a complete PDF service manual for the 97 ZJ, would you? It would be nice to be able to compare the electrical systems on paper... Everything is just electrical signals, and I'm wondering if - If I can find the signal wires into the engine for the existing gauge cluster, if they can just be adapted into the harness for the CRD.
The speed signal would come from the transfer case or the back end of the transmission, I already know where that wire is on my ZJ, I had to pull it temporarily on another ZJ. Long story.
So then it would just be the tach, the water temp is easy, and the oil pressure is easy. Battery and fuel shouldn't change at all either. So really... It is just the speed and tach signals that I would need to trace. Hmm, this might be possible after all.
I understand about the EVIC system, but really... I haven't trusted the MPG reading for YEARS anyway, since the EVIC says that it is getting 18+ on the highway... And I calculate no more than 14-15. This is one of the older ones that didn't have TPMS (thankfully) and only does trip time, MPG avg, mpg instant (if either could be trusted) compass and temp. I use the compass and temp more than anything else.
The last bit of tech is the idiot system below the AC controls. I really wouldn't cry much if I lost that, it whines ever time the stupid washer fluid gets low!
What else does the BCM control? I kinda like the rest of the power goodies in the ZJ, and for the moment... They all work. I even have a check-engine light to wire in if I have to, but what about the OBD plug? Is that routed to the ECM, or the BCM?
Do you know where the tach signal could be found on the CRD's harness? What about a start signal? Is it just as simple as a power signal to the ECM from the key, and then a manually-controlled solenoid to the starter?
I know that the diesel should be a "air plus fuel plus spin = fire" system... But the tech around it is what makes the fun. This might actually be possible...