Suzuki Swift Sport 2004 Service & Repair Manual page 110

1A-60 Engine General Information and Diagnosis:
Step
4 MAF sensor output voltage check
1) Turn OFF ignition switch.
2) Remove ECM from its bracket with ECM connectors
connected.
3) Measure voltage between "C37-26" and "C37-27"
terminals of ECM connector referring to "MAF and IAT
Sensor On-Vehicle Inspection in Section 1C".
Is each value within specified range?
5 MAF sensor power supply voltage check
1) Disconnect connector from MAF and IAT sensor with
ignition switch turned OFF.
2) Turn ON ignition switch, measure voltage between
engine ground and "BLK/RED" wire terminal (2) of MAF
and IAT sensor connector (1).
Is voltage 10 – 14 V?
6 MAF sensor ground circuit check
1) Turn OFF ignition switch, measure resistance between
"GRY" wire terminal of MAF and IAT sensor connector
and engine ground.
Is resistance below 5
7 Ground circuit check
1) Measure resistance between "C37-27" terminal of ECM
connector and vehicle body ground.
Is resistance below 5
8 MAF sensor signal circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Turn ON ignition switch, measure voltage between
"GRN/BLK" wire terminal of MAF and IAT sensor
connector and engine ground.
Is voltage 0 V?
9 MAF sensor signal circuit check
1) Turn OFF ignition switch, measure resistance between
"GRN/BLK" wire terminal of MAF and IAT sensor
connector and engine ground.
Is resistance infinity?
Action
Ω
?
Ω
?
Yes
Poor "C37-26" and/or
"C37-27" terminal
connection.
If OK, substitute a
known-good ECM and
recheck.
Go to Step 6.
I4RS0A110020-01
Go to Step 8.
"GRY" wire is open or
high resistance circuit.
Go to Step 9.
Go to Step 10.
No
Go to Step 5.
"BLK/RED" wire is open
circuit.
Go to Step 7.
ECM grounds "E23-31",
"C37-58", "C37-15" and/
or "C37-30" circuit is
open or high resistance.
If wires are OK,
substitute a known-
good ECM and recheck.
"GRN/BLK" wire is
shorted to other circuit.
"GRN/BLK" wire is
shorted to ground
circuit.