Electrical Tests For The Mpem - Sea-doo Speedster 5894 Shop Manual

Section 08 ELECTRICAL
Sub-Section 06 (MPEM (MULTI-PURPOSE ELECTRONIC MODULE))
RPM Limiter
It has 4 functions :
• Keeps high voltage away from safety lanyard
switch.
• Provides engine stop by shorting the ignition
system generator coil on 717 engine and using
the MPEM on the 787 engine.
• Limits engine RPM to 3500 when shifter is in
neutral position.
• Limits engine RPM to prevent overreving at full
throttle when in forward or reverse.
ELECTRICAL TESTS FOR THE
MPEM
The following gives general electrical-related
problems, for ignition problems, refer to IGNI-
TION SYSTEM
08-03.
General
To ease working, the engine compartment cover
may be removed. Also, the electrical box may be
removed from its mounting location then laid flat
on engine. For that, loose cable retaining nuts and
pull cables out of electrical box.
Always use resistor type spark plugs, otherwise
RFI (Radio Frequency Interference) might affect
MPEM operation.
If there is an electrical problem, first check battery
condition. Never use a battery charger to tempo-
rarily substitute the battery ; this might give erratic
operation or no operation at all.
Check the MPEM supply fuse (2 on Speedster).
Then, make sure to visually inspect all wirings,
connections and fuse tightness.
Wire numbers and connector positions refer to
wiring diagram.
When replacing a MPEM, always have bat-
tery(ies) disconnected.
Prior to replacing a MPEM, always check electri-
cal connections. Disconnecting and reconnecting
the MPEM may cure a "defective" module. The
voltage and current may be to low to flow across
dirty wire terminals. Carefully inspect terminals
for moisture, corrosion or dull appearance. Clean
properly then apply silicone dielectric grease
when reassembling.
08-06-2
Speedster Only
– Both batteries must be properly connected.
Never alter connections of batteries. They are
connected in parallel.
– Electric systems are simply doubled, 2 ignition
coils, 2 starting solenoids, 2 charging systems
etc. Basically the components (ignition coil, rec-
tifier / voltage regulator, starting solenoid etc.)
located on one side belong to the engine of the
same side (ex : ignition coil located on port side
(LH) belongs to the port side engine).
– In the electrical system, basically the same
wire colors are used for starboard (RH) and port
(LH) sides. To differentiate sides, the starboard
(RH) side wires have an additional GREEN trac-
er on the main wiring harness and on the
MPEM.
All Models
IMPORTANT : The following troubleshooting pro-
cedures will apply if the problem is not due to one
of the above items.
DESS Post
If it is impossible to stop engine with safety lan-
yard, check BLACK / RED / GREEN wire (addition-
al BLACK /RED wire for port side (LH) of
Speedster) connection first.
Disconnect DESS post connector behind dash-
board to check its operation. Using an ohmmeter,
take a resistance reading between BLACK and
BLACK /YELLOW of DESS post wires. When
safety lanyard cap is not over its post, the resis-
tance reading should be greater than 20 MW.
When cap is over post, the reading should be not
greater than 1 W.
When safety lanyard cap is on its post, it is possi-
ble to check wiring continuity between positions
no. N and no. dd of the electrical box connector.
The wire position of the electrical box connector
should also be checked. The BLACK / YELLOW
wire from the MPEM is in position no. dd, and the
BLACK wire, also from the MPEM, is in position
no. N.