Suzuki 2000 Grand Vitara SQ625 Service Manual page 54

6-50 ENGINE DIAGNOSIS (G16 / J20 ENGINES)
TROUBLESHOOTING
STEP
1 Was "ENGINE DIAG. FLOW TABLE" performed?
2 Check ECT Sensor and Its Circuit.
1) Connect scan tool with ignition switch OFF.
2) Turn ignition switch ON.
3) Check engine coolant temp. displayed on scan
tool.
Is –40_C (–40_F) or 164_C (327_F) indicated?
3 Check Wire Harness.
1) Disconnect ECT sensor connector with ignition
switch OFF.
2) Check for proper connection to ECT sensor at
"Or /B" and "Bl" wire terminals.
3) If OK, then with ignition switch ON, is voltage
applied to "Or/B" wire terminal about 4 – 6 V?
4 Does scan tool indicate –40_C (–40_F) at Step 2?
5 Check Wire Harness.
1) Disconnect ECT sensor connector.
2) Check intake air temp. displayed on scan tool.
Is –40_C (–40_F) indicated?
6 Check Wire Harness.
1) Using service wire, connect ECT sensor
connector terminals.
2) Turn ignition switch ON and check engine
coolant temp. displayed on scan tool.
Is 164_C (327_F) indicated?
ACTION YES
Go to Step 2.
Go to Step 3.
Go to Step 4.
Go to Step 6.
Replace ECT
sensor.
Replace ECT
sensor.
NO
Go to "ENGINE DIAG.
FLOW TABLE".
Intermittent trouble.
Check for intermittent
referring to "Intermittent
and Poor Connection"
in Section 0A.
"Or/B" wire open or
shorted to power, or
poor C51-3-2
connection.
If wire and connection
are OK, substitute a
known-good ECM
(PCM) and recheck.
Go to Step 5.
"Or/B" wire shorted to
ground.
If wire is OK, substitute
a known-good ECM
(PCM) and recheck.
"Bl/W" wire open or
poor C51-3-23
connection.
If wire and connection
are OK, substitute a
known-good ECM
(PCM) and recheck.