Easy Start

The Easy-Start unit is an unusual, but clever, design.  The potting compound was very soft and sticky, yet crumbly.  I accelerated the de-potting process with alcohol (figuring acetone would melt the plastic enclosure).  There was also a conformal coating over the PCB.  The PCB was well-marked with silkscreened component placements.

It uses a Microchip MCP1623 step-up regulator.  A Microchip PIC16F1824 controls timing and sequencing.  A complete parts list is available as a spreadsheet at the end of this page.

Wire Harness Connections to PCB

Outboard Row (starting from capacitor end):

• Red, 12V+ power 

• Yellow/Green, kill button output

• Black, common

• Red/Black, single-phase stator winding (fuel pump power)

Inboard Row (starting from capacitor end):

• Blue/Red, capacitor positive side

• Yellow/Green, kill button input

• Black, common

• White/Black, single-phase stator winding (fuel pump power)

Observations

The following resistor designations were not used: R8, R15, R20, R22, R23, R24, and R26.  Perhaps this design is a subset of something else?

There are two R19s.  I called them R19a and R19b.  One is used in a spot where two resistors are connected in series.  Often, two resistors are used in series when they need to accommodate a higher voltage than a single would withstand (not the case here).

Note: A Bell mA-2000 Hall-effect current probe was used for current measurements.  A multimeter causes too much burden.

U2 makes ~3.8 VDC from the AAA cell to power the PIC when the kill button is momentarily pressed or the Stator’s fuel pump power winding detects rotation (henceforth I'll define as actuation).

Part of the PIC’s firmware operates as a SMPS boost converter to make ~10V (unloaded) for 30 seconds at the 12-volt port when actuated.  The output can source a maximum of ~80 mA into a dead short, and cell voltage drops to ~1.1V when doing so.  The actual ECU draws ~68mA.

With a nominal 1.28V AAA cell, the quiescent draw is < 1 uA. Maximum current draw is ~775 mA while driving 12-volt output into a 200-ohm load.

The AAA cell is charged at ~2.5mA when 13.8 VDC is applied to the 12-volt port.  The charge rate drops to ~1.9 mA when 10.8V is applied.

On-bike testing: 84mA goes into Easy-Start for a few minutes after actuation, dropping to ~4mA thereafter.

Bench testing: After 30 seconds, the Easy-Start draws 24 mA (presumably to charge AAA cell).  Stopped test after 12 minutes with no change in current draw.  At 10 minutes, shorted +12V line to Fan capacitor (blue/red wire) thinking maybe the fan starting has something to do with it -- nope.  Possibly engine running is detected by stator output?