Diregard - that was posted before the response from Haltech came in.
No it doesn't require that
much work. Trans loom isn't even a consideration, since it's going in a car that doesn't require the speed or reverse sensors...
Here's the solution that Matt from Haltech sent me:
Hi Ant – I see your problem, Im looking at one of those harnesses right now and its certainly setup for the S4/S5 engine. Its not a huge deal, you wont have to remove the front cover or anything like that ! The easy thing for you to do is to cut that white 4 pin plug off and wire two new connectors that go to your two crankshaft position sensors. The wire that goes to that connector should be a 4 core shielded wire, the 4 wires inside will be yellow, green, blue and red (on the Haltech side) on the engine you have 2 identical sensors, one reads the 12 pulse signal (and should have a black and green wire attached) and the other reads the single pulse signal (and should have a white and red wire attached). Connect the 4 Haltech wires from within the 4 core shielded wire as follows:
Haltech Yellow – Mazda Black (this is the signal wire on the 12 pulse sensor);
Haltech Blue – Mazda Green (this is the signal ground wire on the 12 pulse sensor);
Haltech Green – Mazda White (this is the signal wire on the 1 pulse sensor);
Haltech Red – Mazda Red (this is the signal ground wire on the 1 pulse sensor)
The only other difference in engines is the oil metering pump, on the S4 engine the OMP is mechanical however on your S5/S6 engine the OMP is electric and therefore you need to wire up (unless you plan on using premix).
Its easy to do and I have attached a wiring diagram for it, the only difficulty is that these 4 wires are currently not in your wiring harness, they are easy to add in – shoot me over your address and I can send you some pins and wire so you can add these wires to the harness. Basically what you need to add in are the 4 stepper motor wires (in most applications these wires are used for idle control, mazda does not use a 4 wire idle motor so they don’t get used for idle speed on a rotary engine which is good because it means we can use them to control the OMP). These wires will be added into pins 31,32,33 and 34 of the larger connector that goes to the Haltech ECU. Adding these wires is quite simple, just disconnect the ECU from the harness, there is a white locking tab on the connector (on one side of the connector is 1 tab, on the other side its 2 tabs) depress the lock tab on the side of the connector that has the single tab it should move about 1/8th of an inch you now just push the new wires that im going to send you into the back of the connector in the correct location (if you look closely at the back of the connector the pin locations are numbered at each end). Once all 4 wires are insterted push the two lock tabs back in place (if the tabs don’t click back in place easily its likely one of the pins is not located deep enough in the connector preventing the tab from locking). You will see on the diagram that for the OMP feedback you will need to also send 5V and ground plus one of the AVIs to the OMP the 5V and Gnd you can get from the 4 pin trim connector which is near the ECU (all ground wires in the harness are black/white and all 5V wires are orange) – you don’t have to use AVI3, any AVI can be used just be sure to set whichever AVI you do use as the OMP feedback in the software.
Clear as mud now?
If you have any further questions please don’t hesitate to get back to me.
International Project Manager
Haltech Engine Management Systems