2001 NISSAN ALMERA coolant temperature

SEF594K
DescriptionNJEC0649The engine coolant temperature sensor is used to detect the
engine coolant temperature. The sensor modifies a voltage signal
from the ECM. The modified signal returns to the ECM as the
engine coolant temperature input. The sensor uses a thermistor
which is sensitive to the change in temperature. The electrical
resistance of the thermistor decreases as temperature increases.
SEF012P

Engine coolant tempera-
ture ÉC (ÉF)Voltage* (V) Resistance (kW)
þ10 (14) 4.4 7.0 - 11.4
20 (68) 3.5 2.1 - 2.9
50 (122) 2.3 0.68 - 1.00
90 (194) 1.0 0.236 - 0.260
*: These data are reference values and measured between ECM terminal 347
(Engine coolant temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.
On Board Diagnosis LogicNJEC0650
DTC Malfunction is detected when ... Check Items (Possible Cause)
P0115
0103+An excessively high or low voltage from the sen-
sor is entered to ECM.+Harness or connectors (The sensor circuit is
open or shorted.)
+Engine coolant temperature sensor
SEF817Y
DTC Confirmation ProcedureNJEC0651WITH CONSULT-IINJEC0651S011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 5 seconds.
4) If DTC is detected, go to ªDiagnostic Procedureº, EC-683.
WITHOUT CONSULT-IINJEC0651S021) Turn ignition switch ªONº and wait at least 5 seconds.
2) Turn ignition switch ªOFFº, wait at least 5 seconds and then
turn ªONº.
DTC P0115 COOLANT TEMP SENYD
Description
EC-680

Diagnostic ProcedureNJEC0653
1 CHECK ECTS POWER SUPPLY CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect engine coolant temperature sensor harness connector.
SEF382Y
3. Turn ignition switch ªONº.
4. Check voltage between ECTS terminal 2 and ground with CONSULT-II or tester.
SEF401Y
OK or NG
OK©GO TO 2.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
2 CHECK ECTS GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between ECTS terminal 1 and engine ground. Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 4.
NG©GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the following harness for open or short between ECM and engine coolant temperature sensor.
©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0115 COOLANT TEMP SENYD
Diagnostic Procedure
EC-683

4 CHECK ENGINE COOLANT TEMPERATURE SENSOR
1. Remove engine coolant temperature sensor from the engine.
2. Check resistance between ECTS terminals 1 and 2 as shown in the figure.
SEF304X
OK or NG
OK©GO TO 5.
NG©Replace engine coolant temperature sensor.
5 CHECK INTERMITTENT INCIDENT
Refer to ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-665.
©INSPECTION END
DTC P0115 COOLANT TEMP SENYD
Diagnostic Procedure (Cont'd)
EC-684

DescriptionNJEC0660SYSTEM DESCRIPTIONNJEC0660S01
Sensor Input signal to ECM ECM function Actuator
Vehicle speed sensor Vehicle speed
Cooling fan
controlCooling fan relay Engine coolant temperature sensor Engine coolant temperature
Air conditioner switch Air conditioner ªONº signal
The ECM controls the cooling fan corresponding to the vehicle speed, engine coolant temperature, air condi-
tioner ON signal. The control system has 3-step control [HIGH/LOW/OFF].
OPERATIONNJEC0660S02
SEF421Z
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0661Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
AIR COND SIG+Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)ON
COOLING FAN+When cooling fan is stopped. OFF
+When cooling fans operate at low speed. LOW
+When cooling fans operate at high speed. HIGH
ECM Terminals and Reference ValueNJEC0662Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA(DC Voltage)
219 LG/R Cooling fan relay (Low)[Engine is running]
+Cooling fans are not operatingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
+Cooling fans are operatingApproximately 0.1V
DTC P1217 OVER HEATYD
Description
EC-730

TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA(DC Voltage)
221 LG/B Cooling fan relay (High)[Engine is running]
+Cooling fans are not operating
+Cooling fans are operating at low speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
+Cooling fans are operating at high speedApproximately 0.1V
On Board Diagnosis LogicNJEC0663This diagnosis continuously monitors the engine coolant temperature.
If the cooling fan or another component in the cooling system malfunctions, engine coolant temperature will
rise.
When the engine coolant temperature reaches an abnormally high temperature condition, a malfunction is
indicated.
DTC Malfunction is detected when ... Check Items (Possible Cause)
P1217
0208+Cooling fan does not operate properly (Overheat).
+Cooling fan system does not operate properly
(Overheat).
+Engine coolant was not added to the system using
the proper filling method.+Harness or connectors
(The cooling fan circuit is open or shorted.)
+Cooling fan
+Radiator hose
+Radiator
+Radiator cap
+Water pump
+Thermostat
+Engine coolant temperature sensor
For more information, refer to ªMAIN 12 CAUSES OF
OVERHEATINGº, EC-756.
CAUTION:
When a malfunction is indicated, be sure to replace the coolant following the procedure in the LC-44,
ªChanging Engine Coolantº. Also, replace the engine oil.
1) Fill radiator with coolant up to specified level with a filling speed of 2 liters per minute. Be sure
to use coolant with the proper mixture ratio. Refer to MA-18, ªEngine Coolant Mixture Ratioº.
2) After refilling coolant, run engine to ensure that no water-flow noise is emitted.
DTC P1217 OVER HEATYD
ECM Terminals and Reference Value (Cont'd)
EC-731

AEC640
SEF111X
SEC163BA
MEC475B
Overall Function CheckNJEC0664Use this procedure to check the overall function of the cooling fan.
During this check, a DTC might not be confirmed.
WARNING:
Never remove the radiator cap when the engine is hot. Serious
burns could be caused by high pressure fluid escaping from
the radiator.
Wrap a thick cloth around the cap. Carefully remove the cap
by turning it a quarter turn to allow built-up pressure to
escape. Then turn the cap all the way off.
WITH CONSULT-IINJEC0664S011) Check the coolant level in the reservoir tank and radiator.
Allow engine to cool before checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to ªDiagnos-
tic Procedureº, EC-735.
2) Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to ªDiagnos-
tic Procedureº, EC-735.
3) Turn ignition switch ªONº.
4) Perform ªCOOLING FANº in ªACTIVE TESTº mode with CON-
SULT-II and make sure that cooling fans operate when touch-
ing ªHIGHº or ªLOWº.
If NG, go to ªDiagnostic Procedureº, EC-735.
WITHOUT CONSULT-IINJEC0664S021) Check the coolant level in the reservoir tank and radiator.
Allow engine to cool before checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to ªDiagnos-
tic Procedureº, EC-735.
2) Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to ªDiagnos-
tic Procedureº, EC-735.
3) Start engine.
Be careful not to overheat engine.
4) Set temperature control lever to full cold position.
5) Turn air conditioner switch ªONº.
6) Turn blower fan switch ªONº.
7) Run engine at idle for a few minutes with air conditioner oper-
ating.
Be careful not to overheat engine.
8) Make sure that cooling fans operate at low speed.
9) Turn ignition switch ªOFFº.
10) Turn air conditioner switch and blower fan switch ªOFFº.
11) Disconnect engine coolant temperature sensor harness con-
nector.
12) Connect 150Wresistor to engine coolant temperature sensor
harness connector.
13) Start engine and make sure that cooling fans operate at higher
speed than low speed.
Be careful not to overheat engine.
14) If NG, go to ªDiagnostic Procedureº, EC-735.
DTC P1217 OVER HEATYD
On Board Diagnosis Logic (Cont'd)
EC-732

5 CHECK COOLING FAN HIGH SPEED OPERATION
Without CONSULT-II
1. Turn ignition switch ªOFFº.
2. Reconnect cooling fan relays-2 and -3.
3. Turn air conditioner switch and blower fan switch ªOFFº.
4. Disconnect engine coolant temperature sensor harness connector.
5. Connect 150Wresistor to engine coolant temperature sensor harness connector.
6. Restart engine and make sure that cooling fans-1 and -2 operate at high speed.
MEC475B
OK or NG
OK©GO TO 6.
NG©Check cooling fan high speed control circuit. (Go to PROCEDURE B, EC-743.)
6 CHECK COOLING SYSTEM FOR LEAK
Apply pressure to the cooling system with a tester, and check if the pressure drops.
Testing pressure: 157 kPa (1.57 bar, 1.6 kg/cm2, 23 psi)
CAUTION:
Higher than the specified pressure may cause radiator damage.
SLC754A
Pressure should not drop.
OK or NG
OK©GO TO 8.
NG©GO TO 7.
7 DETECT MALFUNCTIONING PART
Check the following for leak.
+Hose
+Radiator
+Water pump (Refer to LC-39, ªWater Pumpº.)
©Repair or replace.
DTC P1217 OVER HEATYD
Diagnostic Procedure (Cont'd)
EC-738

10 CHECK ENGINE COOLANT TEMPERATURE SENSOR
1. Remove engine coolant temperature sensor.
2. Check resistance between engine coolant temperature sensor terminals 1 and 2 as shown in the figure.
SEF304X
OK or NG
OK©GO TO 11.
NG©Replace engine coolant temperature sensor.
11 CHECK MAIN 12 CAUSES
If the cause cannot be isolated, go to ªMAIN 12 CAUSES OF OVERHEATINGº, EC-756.
©INSPECTION END
Procedure ANJEC0666S0301
1 CHECK COOLING FAN POWER SUPPLY CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect cooling fan relay-1.
3. Turn ignition switch ªONº.
4. Check voltage between cooling fan relay-1 terminals 1, 3, 6 and ground with CONSULT-II or tester.
SEF590X
OK or NG
OK©GO TO 3.
NG©GO TO 2.
DTC P1217 OVER HEATYD
Diagnostic Procedure (Cont'd)
EC-740