Suzuki Ignis Service Manual page 3371

6-170 ENGINE GENERAL INFORMATION AND DIAGNOSIS
TROUBLESHOOTING
Step
1 Check each injector for operating sound at
engine cranking using sound scope.
Do all 4 injector make operating sound?
2 Check fuel injector resistance.
1) Disconnect connectors from fuel injectors
with ignition switch turn OFF.
2) Check for proper connection to fuel injector
at each terminals.
3) If OK, check all 4 fuel injectors for resis-
tance, referring to "Fuel injector inspection"
in Section 6E1.
Are all injectors in good condition?
3 Check fuel injector insulation resistance.
1) Check that there is insulating between each
fuel injector terminals and engine ground.
Is there insulating?
4 Check fuel injector power supply.
1) Measure voltage between each "BLK/RED"
wire terminal and engine ground with igni-
tion switch turned ON.
Is voltage 10 – 14 V?
5 Check wire circuit.
1) Turn OFF ignition switch.
2) Disconnect connectors from ECM.
3) Measure resistance between each "BLU/
YEL", "BLU/WHT", "BLU/RED", "BLU/GRN"
wire terminal and vehicle body ground.
Is resistance infinity?
6 Check wire circuit.
1) Measure voltage between each "BLU/YEL",
"BLU/WHT", "BLU/RED", "BLU/GRN" wire
terminal and vehicle body ground with igni-
tion switch turned ON.
Is voltage 0 V?
7 Check fuel injector drive signal.
1) Connect connectors to each fuel injectors
and ECM with ignition switch turned OFF.
2) Turn ON ignition switch.
3) Measure voltage "C63-7", "C63-6", "C63-5",
"C63-4" terminal and vehicle body ground.
Is voltage 10 – 14 V?
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.
Go to Step 7.
Check fuel injector, refer-
ring to "Fuel injector
inspection" in Section
6E1.
If result in good condition,
substitute a known-good
ECM and recheck.
No
Go to Step 2.
Faulty fuel injector.
Faulty fuel injector.
"BLK/RED" wire in open
circuit or shorted to
ground circuit.
If it is in good condition,
go to diag flow table A-3.
"BLU/YEL", "BLU/WHT",
"BLU/RED", "BLU/GRN"
wire shorted to ground.
"BLU/YEL", "BLU/WHT",
"BLU/RED", "BLU/GRN"
wire shorted to power
supply circuit.
"BLU/YEL", "BLU/WHT",
"BLU/RED", "BLU/GRN"
open circuit.