Tacho feed from ecu?? - Ford Forums

Lucus · 09-23-2005, 01:41

Hey guys need some help...have fitted a turbosmart eboost2 to my ute but i need a tach feed from the ecu to provide a rpm reference for boost mapping controlled by the engine rpm.....long story short anybody know the pin#/wire colour for the tach feed from the ecu??
thanks in advance

Moses · 09-25-2005, 23:27

rpm signal is on CAN-bus. it is a digital signal placed onto the CAN by the PCM and used by various modules, including the IC. So in short you have CAN+ and CAN- circuits into the IC but no dedicated Tacho pin.

Lucus · 09-26-2005, 06:17

forgive my ignorance but can-bus??? the unit needs a square wave(digital) signal between 0 and 12 volts...is that avaliable without using a convertor?
thanks in advance mate...

Moses · 09-27-2005, 05:04

CAN-bus is the digital network that makes module comunication faster and more reliable. It is made up of twisted pair wires, one for CAN high the other for CAN low. Information such as the RPM signal which is required for things such as tacho on instrument cluster is transmitted as binary information and picked up by the modules that need it. So unless you know the binary code used for RPM signal your chances of using it for the purpose you desire are fairly minimal. The only other option is if you can pick up the signal direct from the CKP sensor (make sure the pick-up used is run in parallel to the CKP circuit) and run it through an analogue to digital converter as the CKP signal is an A/C sine wave not digital square wave.