Ariens Sno-Thro Platinum Series Service Manual page 78

recoil starter handle to check for spark. If no spark
is present, replace spark plug.
f. Reinstall spark plug and finger tighten. Turn an
additional 1/4 turn after spark plug is seated.
g. Reinstall spark plug wire and make sure it is
correctly positioned onto the spark plug.
3. Check the battery. Battery should have 7.2 V DC – 8.4
V DC, depending on when the battery was most
recently charged. Extremely low voltage could prevent
the ECU from triggering a trouble code and result in a
no-start condition. If battery has low voltage, connect
battery charger to battery. Also check the inline fuse
on the battery cable.
If battery measures below specification after charging,
replace battery.
4. Check wire harness connection to the ECU.
a. With the ignition key in the off position, check the
wire harness connections to the ECU. If
connections are secure, disconnect the 12-pin
and 14-pin connections to the ECU and inspect
connectors for bad connections or burn marks.
b. Check that all wire terminals are snug in their
connectors. If connections appear to be good,
reconnect wire harness and start engine to check
if issue is still present. If bad connection is
present, replace wire harness.
c. If issue is still present, advance to next step.
5. Check the ECU.
a. Disconnect wire harness from ECU and test with a
new ECU to verify the original ECU is not cause
for malfunction. If malfunction is not resolved with
a new ECU, reconnect wire harness to original
ECU and continue diagnostics.
6. Check the ECU status. With battery voltage between
7.2 V DC – 8.4 V DC, check if the green ECU status
light is blinking at a consistent rate.
If battery measures below 7.2 V DC,
IMPORTANT:
ECU LEDs may appear dim or will not illuminate red
or green LEDs.
If green LED is constant, (not-blinking)
see
EFI Trouble Code Identification on page 71.
7. Check fuel pump output.
a. Remove the heater box.
b. Check voltage at fuel pump. See Code 27: Low
Fuel Pressure on page 73 for voltage readings.
c. Remove fuel hose from fuel pump outlet and
attach a suitable length of fuel hose to the fuel
pump outlet that can safely reach a clearly marked
fuel container.
d. With battery voltage between 7.2 V DC – 8.4 V
DC, turn the key to the ON position for 10 seconds
to pump fuel into the container. Fuel should
measure approximately 160 mL (5 oz.).
If fuel amount measures less than 160 mL, remove the fuel
pump and check the pre-filter for blockage. If filter is clean,
replace fuel pump. See Figure 191.
IMPORTANT: If replacing fuel pump, wet the fuel system:
a. Fill fuel tank full.
b. Cycle ignition key to the ON position, then to the
OFF position. Repeat.
IMPORTANT: Cycling the ignition key multiple times may
inject excessive amounts of fuel into the throttle body and
"flood" the engine. A flooded engine may require more
starting attempts than normal.
8. Remove connector to the injector.
a. Move gray slide upward until it stops. Gently
compress gray slide and remove connector. See
Figure 192.
b. Set a multi-meter to V DC and probe each
terminal with the red probe and contact the black
probe against the engine block. With the ignition
key in the ON position, each terminal should
measure 7.2 V DC – 8.4 V DC. See Figure 193.
EN – 76
Pre- Filter
Figure 191
Figure 192
Gray
Slide