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Pin B16 unterminated M800 harness

PostPosted: Mon Aug 10, 2009 5:46 am
by speedrr
Hello,
As stated last time, I am attempting to build a wire harness for my Motec M800 to be installed on my street 88 BMW E30 M3. A quick disclaimer on my part - this is a totally new learning experience for me! I am going to run sequential injectors and COPs. Both the Ref and Sync sensors are magnetic. When attempting to understand the two shielded cables on the unterminated harness I observed the following:
1. Three wires exit the unterminated end of the both the sync and ref cable, a white wire, a white/orange wire and a white/blue wire.
2. The ref and sync are taped together at the Motec end with the following wires existing the joined cables - 1 white wire labled ref, 1 white wire labled sync, 2 white/orange wires, 2 white/blue wires and 2 white/black wires.
I assume the 2 white/black wires splice into the shield. The 2 white/blue wires and the 2 white/black wires are spliced together along with 11 brown wires. One of the brown wires goes to Pin B15 (0v Aux). Should this not go to Pin B16(0v Engine)? The M800 wiring diagram shows B16 for the ref and sync sensors as well as throttle position, manifold pressure, etc. On my harness Pin 16 is a brown wire spliced into 9 brown wires. Should I just switch these two wires on the B connector?
I know the white wire labled ref goes to Pin B1, the white wire labled sync goes to Pin B2. It looks like the white/orange wires are not used with magnetic sensors. Is this correct?
Finally, the connectors for both of my magnetic sensors have 3 pins. The cable running from the sensor to the connector is shielded. Do I simply run a wire to chassis ground for the third pin which is the shielded wire? I know I read somewhere that you only go to ground on the shielded wire at one end, not at the sensor and the ECU. Since the connectors are sealed, is there an easy way to determine which pin is the signal, the 0v engine and the shielded ground.
Thanks in advance!
Tom

Re: Pin B16 unterminated M800 harness

PostPosted: Mon Aug 10, 2009 3:22 pm
by RossB
I would have thought that the 0V wires would have been connected to B16 as well but B16 and B15 are internally connected so this won't make any difference. The white/orange wires should be connected to A12, this is the 8V supply which is only used for Hall sensors so you do not need to use this as you say.
You could connect the shield on the loom to the shield on the sensor. On your crank sensor you should find 2 pins that have continuity between them. These are the ones you need to use for the signal and 0V, the other is the shield. The polarity of the sensor doesn't really matter as this can be changed in the ref/sync setup in ECU Manager.

Re: Pin B16 unterminated M800 harness

PostPosted: Mon Aug 10, 2009 10:06 pm
by speedrr
Thanks RossB!