Dtc P0116: Engine Coolant Temperature Circuit Range / Performance - Suzuki Swift Sport 2004 Service & Repair Manual

1A-76 Engine General Information and Diagnosis:
Step
8 Ground circuit check
1) Remove ECM from its bracket with ECM connectors
connected.
2) Measure resistance between "C37-55" terminal of ECM
connector and vehicle body ground.
Is resistance below 5
9 IAT sensor for performance check
1) Check IAT sensor according to "MAF and IAT Sensor
Inspection in Section 1C".
Is it in good condition?

DTC P0116: Engine Coolant Temperature Circuit Range / Performance

Wiring Diagram
1
15 14 13 12 11
30 28 27 26
29
45 44 43 42 41
59
60 58 57 56
1. ECT sensor
DTC Detecting Condition and Trouble Area
DTC detecting condition
ECT sensor values is less than –5 °C, 23 °F while engine is
running under more than specified engine load (more than 1000
rpm) for 2 to 1116 min (depending on ECT at engine start)
continuously from engine start.
(*2 driving cycle detecting logic, monitoring once per driving
cycle)
Action
Ω
?
LT GRN
ORN
3
E23
10 9 8 7 6 5 4 3
25 24 23 22 21 20 19 18
40 39 38 37 36 35 34 33
55 54 53 52 51 50 49 48
2. ECM
"GRY/BLU" wire and/or
"ORN" wire is open
circuit or high resistance
circuit. Poor "C37-55"
connection.
Substitute a known-
good ECM and recheck.
C37-24
C37-55
ORN
2 1 15 14 13 12 11
17 16 30 28 27 26
29
32 31 45 44 43 42 41
59
47 46 60 58 57 56
• ECT sensor
• ECT sensor circuit
• Thermostat
• ECM
Yes
Faulty ECM ground
circuit. If circuit is OK,
substitute a known-
good ECM and recheck.
Replace MAF and IAT
sensor.
5V
2
C37
10 9 8 7 6 5 4 3
25 24 23 22 21 20 19 18
40 39 38 37 36 35 34 33
55 54 53 52 51 50 49 48
3. To other sensors
Trouble area
No
S7RS0B1104026
2 1
17 16
32 31
47 46
I4RS0A110025-01