Mercury 150 EFI Service Manual page 79

IGNITION
Symptom
1. Engine cranks but will
not start (continued)
2. Engine cranks, starts
and stalls
Page 2A-22
Cause
1.7 ECM not functioning
1.8 Crank Position Sensor not
functioning
2.0 Abnormally high friction in
engine
2.1 Air in fuel system/lines
2.2 TPS malfunction
2.3 Remote control to engine
harness connection is poor
Action
Check for proper operation by
using Inductive Timing Light
91-99379.
Check battery voltage
(RED/YEL Lead) @ ignition
coils.
Check for blown fuse (C15).
Check battery voltage to fuse
from main power relay
(PURPLE Lead).
Check for shorted stop wire
(BLK/YEL).
Check crank position sensor
setting [0.025 in. – 0.040 in.
(0.64 mm – 1.02 mm)] from
flywheel or for defective crank
position sensor.
Defective ECM.
Power Supply:
Clean and inspect remote control
male and female harness connec-
tors.
– Sensor faulty.
– Bad connection
– Air gap incorrect
Check for scuffed piston or other
sources of high friction.
Crank and start engine several
times to purge.
Check motion of throttle arm. Stop
nuts should contact block at idle
and WOT. Check TPS set-up. Must
connect DDT with adapter harness
(84-822560A5) to ECM.
Clean and inspect male and fe-
male connectors.
90-883728 JULY 2001