Fuel Injection System Troubleshooting - Suzuki GF60A Service Manual

1G-14 Fuel System:

Fuel Injection System Troubleshooting

Before starting the troubleshooting, make sure that:
• There is no self-diagnostic code indication.
• Emergency stop switch plate is set in place.
Step
1 Check fuel injector operating sound.
• Check each injector for operating sound at engine
cranking. ( (Page 1G-22))
Do all 3 injector make operating sound?
2 Check fuel injector resistance.
• Turn ignition switch off, disconnect connectors from fuel
injectors.
• Check for proper connection to fuel injector at each
terminal.
• If good condition, check all fuel injector for resistance.
( (Page 1G-22))
Are all injectors in good condition?
3 Check fuel injector power supply.
• Measure voltage between each "Gray" wire terminal of
fuel injector connector and engine body ground with
ignition switch turned "ON".
Is voltage 10 – 14 V?
4 Check Wire circuit.
• Turn "OFF" ignition switch.
• Disconnect connector from ECM.
• Measure resistance between each "O/B", "B/Br", "R/W"
wire terminal of the fuel injector connector and body
ground.
Is resistance infinity?
5 Check Wire circuit.
• Connect connector to ECM.
• Measure voltage between each "O/B", "B/Br", "R/W" wire
terminal of fuel injector connector and body ground with
ignition switch turned "ON".
Is voltage 0 V?
6 Check fuel injector operating signal.
• Connect connectors to each fuel injector and ECM with
ignition switch turned "OFF".
• Measure fuel injector operating signal between each "45",
"71", "47" terminal of ECM and body ground. ( (Page
1G-23))
Is voltage 4 – 10 V or over?
Action Yes
Fuel injector circuit is in
good condition.
Go to step 3.
Go to step 4.
Go to step 5.
Go to step 6.
If check result is
satisfactory, substitute a
known-good ECM and
recheck.
ZAJ6111704003
No
Go to step 2.
Faulty fuel injector.
• "Gray" wire open or
shorted.
• If it is in good
condition, check ECM
power source and
ground circuit.
"O/B", "B/Br" and/or "R/
W" wire(s) are shorted
to ground.
"O/B", "B/Br" and/or "R/
W" wire(s) are shorted
to power supply circuit.
"O/B", "B/Br" and/or "R/
W" wire(s) are open
circuit.