BRP E 250 L HO AG B, Service Manual

Page: 83 / 460

83
Engine and Control Systems
Engine Control Systems
4
Crankshaft Position Sensor
Ribs spaced on the flywheel mark crankshaft posi-
tion. As the ribs pass the magnetic field of the
CPS, an AC voltage signal is generated. The
EMM uses this signal to identify crankshaft posi-
tion and speed, generate a tachometer signal, and
control fuel and ignition timing.
If the sensor is damaged or the signal is intermit-
tent:
•
Below 2000 RPM: 5 occurrences
•
Above 2000 RPM: 1 occurrences
the EMM :
Approximate air gap between CPS and flywheel
encoder ribs is 0.073 (1.85 mm).
Use the Evinrude Diagnostics software Monitor
screen to check CPS operation. The software
should show an RPM reading while the outboard
is cranking. If the CPS or its circuit fails, no RPM
reading will appear and the outboard cannot run.
Knock Sensor
Knock sensors (one per cylinder head) detect the
presence of knock (pre-ignition or detonation)
during the combustion cycle.
When knock is detected, the EMM temporarily
increases fuel flow and retards ignition timing for
the affected cylinder.
If knock continues, the EMM :
If the EMM detects the knock sensor circuit is
OPEN, the EMM :
Internal EMM Functions
ROM Verification
The EMM performs a self-test of programming
every time it is turned ON. Fault code 15 indicates
a programming (software) issue. Reprogram the
EMM with the correct software program to correct
the problem.
Start Assist Circuit (SAC)
When the ignition key is ON, the EMM Start Assist
Circuit (SAC) boosts battery voltage (12 V) to
30 V on the system (55 V) circuit.
If the SAC circuit current exceeds 2 Amps, or if the
SAC voltage is less than 20 V, the
EMM :
Idle Controller
The idle controller reacts to engine operating con-
ditions. Fuel and ignition timings are altered to
maintain a specific RPM when engine is cold or
warm. The controller is inactive when the TPS is
advanced from idle position.
Electronic Throttle Controller
Refer to Electronic Throttle Controller on p. 84.
Electronic Shift Controller
Refer to Electronic Shift Controller on p. 86.
Dynamic Power Steering
Refer to Dynamic Power Steering (DPS) on
p. 301.
Stores fault code 16
Activates S.A.F.E.
Stores fault code 1-6 (code indicates cyl)
Engine Monitor: CHECK ENGINE display ON
Stores fault code 7 (port sensor)
Stores fault code 8 (starboard sensor)
Engine Monitor: CHECK ENGINE display ON
Stores fault code 77