Below is the wiring for the Crane XR700 optical trigger
driving the MegaSquirt ECU and using the Crane box to drive the coil.
In this configuration, the Crane optical trigger drives
the MS v2.2 and the FIdle out drives the Crane amplifier that in turn
drives the coil. The Crane XR700 does not have any intelligence, so
it is best to use the MSnS-Extra dwell control.
- Remove D5, R10
- Remove jumper between XG1 and XG2
- Replace D8 with a 1.3 (or 1.3 to 2kohm) resistor 1/2 Watt or greater.
- Fit a wire between between XG1 and right of D5 (the side that goes
to pin 24/coil)
- Fit wire between bottom of R10 (where R10 and D8 are tied together)
and right side of D9 (+12V)
You can test your input connection by monitoring IRQ-1
at R11. First set up MS to monitor IRQ with the center front panel LED.
Disconnect power to the coil. Put on the hand brake and the car in neutral.
Now turn the engine such that the crank pulley passes from 20º
BTDC to TDC. The IRQ LED should go from On to OFF at ~10º BTDC
for most cars with distributor (but it may be from 5º to 15º,
usually this is called the static timing)