2004 dodge ram diesel tach wire

the factory remote start system i was putting in today at the dealership said the tach wire was a dark blue/grey on the 60 pin connector on the computer... but there is no such wire, i think its because the remote start was for a 2003.... we checked on the internet and in books but couldnt find it, and there's too many wires to probe and plus they are a full arms reach so its almost impossible to test them all, does anybody know the color for this wire or where i can find out??

The PCM is on the passenger side firewall. On diesel models the tach wire is at the ECM on the lower driver side of the engine, 60 pin plug, pin 24.ORANGE connector is where pin 24 is found.

This is all the iinformation that I have for this wire on this truck. Have you tried looking for this wire inside the instrument cluster ?

I just finished my install on that exact truck today. 

The wire you are looking for is Blue -Grey.  I pulled the left front tire (15/16ths) and left inner wheel well ( 7 or 8 mm's I think) out and you can actually get to it very easily.  The connector you want on the ECM is the one on the left, 60 pins, 10 pins to each row.  3rd row down first pin is 21, go three more to the right and you should see it.  After disconnecting the batteries I had to unbolt the Allen screw in the middle of the connector and take out one 10 MM bolt up on the harness.  That allowed me to pull the connector over near the frame rail so I could pull that wire up a little to solder the connection, worked like a charm.  Good luck