Suzuki 2000 Grand Vitara SQ625 Service Manual page 166

D Intake air temperature: between –14_C and 70_C (68_F and 158_F)
D Atmospheric pressure: higher than 560 mmHg (Altitude: lower than 2790 m (9150 ft))
(1) With ignition switch OFF, connect scan tool.
(2) Turn ON ignition switch, clear DTC if any.
(3) Start engine and run it for 10 sec.
(4) Check DTC by using scan tool.
DTC TROUBLESHOOTING
STEP
1 Was "ENGINE DIAG. FLOW TABLE" performed?
2 Check IAT Sensor and Its Circuit.
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ignition switch ON.
3) Check intake air temp. displayed on scan tool.
Is –40_C (–40_F) or 205_C (401_F) indicated?
3 Check Wire Harness.
1) Disconnect IAT sensor connector (1) with ignition
switch OFF.
2) Check for proper connection to IAT sensor at "LBl"
and "Gr/Y" wire terminals.
3) If OK, then with ignition switch ON, is voltage
applied to "LBl" wire terminal about 4.5 – 5.5 V?
4 Does scan tool indicate –40_C (–40_F) at Step 2.
5 Check Wire Harness
1) Check intake air temp. displayed on scan tool with
ignition switch ON.
Is –40_C (–40_F) indicated?
6 Check Wire Harness.
1) Using service wire (2), connect IAT sensor
connector terminals.
2) Check intake air temp. displayed on scan tool with
ignition switch ON.
Is 205_C (401_F) indicated?
Fig. for STEP 3
ACTION
ENGINE (H25 ENGINE) 6-1-55
YES
Go to Step 2.
Go to Step 3.
Go to Step 5.
Go to Step 6.
Replace IAT sensor.
Replace IAT sensor.
Fig. for STEP 6
NO
Go to "ENGINE
DIAG. FLOW
TABLE".
Intermittent trouble.
Check for intermittent
referring to
"Intermittent and
Poor Connection" in
Section 0A.
"LBl" wire open or
shorted to power, or
poor C51-3-8
connection.
If wire and
connection are OK,
substitute a known-
good ECM and
recheck.
Go to Step 5.
"LBl" wire shorted to
ground.
If wire is OK,
substitute a known-
good ECM and
recheck.
"LBl" wire open or
poor C51-3-21
connection.
If wire and
connection are OK,
substitute a known-
good ECM and
recheck.