EGR TEMP SEN/CIRC
COMPONENT DESCRIPTION
The EGR temperature sensor detects temperature changes in the EGR passage way. When the EGR volume control valve opens, hot exhaust gases flow, and the temperature in the passage way changes. The EGR temperature sensor is a thermistor that modifies a voltage signal sent from the ECM. This modified signal then returns to the ECM as an input signal. As the temperature increases, EGR temperature sensor resistance decreases.
This sensor is not directly used to control the engine system. It is used only for the on board diagnosis.
ON BOARD DIAGNOSIS LOGIC
DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE
Perform "Procedure for malfunction A" first. If DTC cannot be confirmed, perform "Procedure for malfunction B".
NOTE: If "DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE" has been previously conducted, always turn ignition switch "OFF" and wait at least 10 seconds before conducting the next test.
Procedure for malfunction A
With Consult
1. Turn ignition switch "ON".
2. Select "DATA MONITOR" mode with CONSULT.
3. Verify that engine coolant temperature is less than 40 °C (104 °F).
If the engine coolant temperature is above the range,cool the engine down.
4. Start engine and let it idle for at least 8 seconds.
5. If 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".
OR
With Generic Scan Tools
1. Turn ignition switch "ON".
2. Select "MODE 1" with GST.
3. Verify that engine coolant temperature is less than 40 °C (104 °F).
If the engine coolant temperature is above the range,cool the engine down.
4. Start engine and let it idle for at least 8 seconds.
5. Select "MODE 7" with GST.
6. If 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".
OR
Without Scan Tools
1. Turn ignition switch "ON".
2. Verify that voltage between ECM terminal (59) (engine coolant temperature) is more 2.7 V.
If the voltage is below the range, cool the engine down.
3. Start engine and let it idle for at least 8 seconds.
4. Turn ignition switch "OFF" and wait at least 10 seconds.
5. Turn ignition switch "ON" and perform "Diagnostic Test Mode (Self-diagnostic results)" with ECM.
6. It 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".
Procedure for malfunction B
CAUTION: Always drive vehicle at a safe speed.
TESTING CONDITION: Always perform the test at a temperature above -10 °C (14 1|F).
With Consult
1. Start engine and warm it up to normal operating temperature.
2. Select "EGR VOL CONT/V" in "ACTIVE TEST" mode with CONSULT.
3. Hold engine speed at 1,500 rpm.
4. Touch "Qu" and set the EGR volume control valve opening to 50 step and check EGR TEMP SEN.
EGR TEMP SEN should decrease to less than 1.0 V.
If the check result is NG, go to "DIAGNOSTIC PROCEDURE".
If the check result is OK, go to the following step.
5. Turn ignition switch "OFF" and wait at least 10 seconds.
6. Start engine and maintain the following conditions for at least 5 consecutive seconds.
CKPS.RPM (POS): 1,800 - 2,800 rpm
VHCL SPEED SE: 10 KPH (6 MPH) or more
B/FUEL SCHDL: More than 3.5 msec
THRTL POS SEN: 0.65 - 1.08 V
Selector lever: Suitable position
7. If 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".
OR
With Generic Scan Tools
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch "OFF" and wait at least 10 seconds,then turn "ON".
3. Select "MODE 1" with GST and maintain the following conditions for at least 5 consecutive seconds.
Engine speed: 1,800 - 2,800 rpm
Vehicle speed: 10 KPH (6 MPH) or more
Voltage between ECM terminal (23) and ground: 0.65 - 1.08 V
Selector lever: Suitable position
4. Select "MODE 3" with GST.
5. If 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".
OR
Without Scan Tools
1. Start engine and it up to normal operating temperature.
2. Turn ignition switch "OFF" and wait at least 10 seconds,then turn "ON".
3. Select "MODE 1" with GST and maintain the following conditions for at least 5 consecutive seconds.
Engine speed: 1,800 - 2,800 rpm
Vehicle speed: 10 KPH (6 MPH) or more
Voltage between ECM terminal (23) and ground: 0.65 - 1.08 V
Selector lever: Suitable position
4. Turn ignition switch "OFF" and wait at least 10 seconds,then turn "ON".
5. Perform "Diagnostic Test Mode II" (Self-diagnostic results) with ECM.
6. If 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".
WIRING DIAGRAM
DIAGNOSTIC PROCEDURE
COMPONENT INSPECTION
EGR temperature sensor
Check resistance change and resistance value.
If NG, replace EGR temperature sensor.