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Symptom:
P-0117 ECT SENSOR VOLTAGE TOO LOW
When Monitored and Set Condition:
P-0117 ECT SENSOR VOLTAGE TOO LOW
When Monitored: With the ignition on.
Set Condition: The engine coolant temperature sensor circuit voltage at PCM cavity 26
goes below .5 volt for more than 3 seconds.
POSSIBLE CAUSES
ECT SENSOR VOLTAGE ABOVE 4.0 VOLTS
ECT SENSOR SIGNAL CIRCUIT SHORT TO GROUND
ECT SENSOR SIGNAL CIRCUIT SHORTED TO GROUND CKT
ECT WIRING HARNESS INTERMITTENT DEFECT
ECT WIRING HARNESS OBSERVABLE DEFECT
PCM DEFECTIVE (ECT SENSOR V LOW)
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
With the DRB, read the Engine Coolant Temperature (ECT) Sensor voltage.
Is the Engine Coolant Temperature Sensor voltage below 0.5 volt?All
Ye s®Go To 2
No®Go To 6
2 Ignition Off
Disconnect the Engine Coolant Temperature (ECT) Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Ignition on, engine not running.
With the DRB, read the Engine Coolant Temperature Sensor voltage.
Is the ECT Sensor voltage above 4.0 volts?All
Ye s®Replace the Engine Coolant Temperature Sensor.
Perform Powertrain Verification Test VER-5A.
No®Go To 3
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DRIVEABILITY
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TEST ACTION APPLICABILITY
3 Ignition Off
Disconnect the Engine Coolant Temperature Sensor (ECT) Connector.
Note: Check connectors - Clean/repair as necessary.
Disconnect the Powertrain Control Module Connector.
Note: Check connectors - Clean/repair as necessary.
With an ohmmeter, measure the resistance between the ECT Sensor Signal Circuit
and the ECT Sensor Ground Circuit.
Is the resistance below 5.0 ohms?All
Ye s®Repair the ECT Sensor Signal Circuit shorted to the ECT Sensor
Ground Circuit.
Perform Powertrain Verification Test VER-5A.
No®Go To 4
4 Ignition Off
Disconnect the Engine Coolant Temperature (ECT) Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Disconnect the Powertrain Control Module Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the ECT Sensor Signal Circuit to ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the ECT Sensor Signal Circuit for a short to ground.
Perform Powertrain Verification Test VER-5A.
No®Go To 5
5 Ignition Off
If there are no potential causes remaining, the PCM is assumed to be defective.
View repair options.All
Repair
Replace the Powertrain Control Module.
Perform Powertrain Verification Test VER-5A.
6 Ignition On, Engine Not Running
Using the schematic, wiggle the ECT Sensor Connector and Harness.
Monitor the DRB display.
Was there any ECT Sensor voltage change?All
Ye s®Repair the Harness or Connector that caused the voltage change.
Perform Powertrain Verification Test VER-5A.
No®Go To 7
7 Ignition Off
Using the schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-5A.
No®Test Complete.
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DRIVEABILITY
P-0117 ECT SENSOR VOLTAGE TOO LOW ÐContinued
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Symptom:
P-0118 ECT SENSOR VOLTAGE TOO HIGH
When Monitored and Set Condition:
P-0118 ECT SENSOR VOLTAGE TOO HIGH
When Monitored: With the ignition on.
Set Condition: The engine coolant temperature sensor circuit voltage at PCM cavity 26
goes above 4.9 volts for more than 3 seconds.
POSSIBLE CAUSES
ECT SENSOR DEFECTIVE
ECT SENSOR GROUND CIRCUIT OPEN
ECT SENSOR SIGNAL CIRCUIT OPEN
ECT SENSOR WIRING HARNESS INTERMITTENT DEFECT
ECT SENSOR WIRING HARNESS OBSERVABLE DEFECT
PCM DEFECTIVE
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
With the DRB, read the ECT Sensor voltage.
Is the ECT Sensor voltage above 4.9 volts?All
Ye s®Go To 2
No®Go To 6
2 Ignition On, Engine Not Running
Disconnect the ECT Sensor.
Note: Check connectors - Clean/repair as necessary.
Connect a jumper wire between the ECT Sensor Signal Circuit and the Sensor
Ground Circuit.
With the DRB, read the ECT Sensor voltage.
Is the voltage below 1.0 volt?All
Ye s®Replace the ECT Sensor.
Perform Powertrain Verification Test VER-5A.
No®Go To 3
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TEST ACTION APPLICABILITY
3 Ignition Off
Disconnect the ECT Sensor Electrical Connector.
Note: Check connectors - Clean/repair as necessary.
Connect a jumper wire between the ECT Sensor Signal Circuit and an engine ground.
Turn the ignition on, with the engine not running.
With the DRB, read the Engine Coolant Temperature Sensor voltage.
Is the voltage below 1.0 volt?All
Ye s®Repair the open ECT Sensor Ground Circuit.
Perform Powertrain Verification Test VER-5A.
No®Go To 4
4 Ignition Off
Disconnect the ECT Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Disconnect the PCM Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the ECT Sensor Signal Circuit from the PCM to the
ECT.
Is the resistance below 5.0 ohms?All
Ye s®Go To 5
No®Repair the open ECT Sensor Signal Circuit.
Perform Powertrain Verification Test VER-5A.
5 Ignition Off
If there are no potential causes remaining, the PCM is assumed to be defective.
View repair options.All
Repair
Replace the PCM.
Perform Powertrain Verification Test VER-5A.
6 Ignition On, Engine Not Running
Use the schematic as a guide and wiggle the ECT Sensor Connector & Harness.
Monitor the DRB display.
Was there any ECT Sensor voltage change?All
Ye s®Repair the Harness or Connector that caused the voltage change.
Perform Powertrain Verification Test VER-5A.
No®Go To 7
7 Ignition Off
Using the schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-5A.
No®Test Complete.
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DRIVEABILITY
P-0118 ECT SENSOR VOLTAGE TOO HIGH ÐContinued
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Symptom:
P-0121 TPS VOLTAGE DOES NOT AGREE WITH MAP
When Monitored and Set Condition:
P-0121 TPS VOLTAGE DOES NOT AGREE WITH MAP
When Monitored: With the engine running and no MAP sensor or TP sensor trouble
codes.
Set Condition: PCM - 2 tests on TPS. High Voltage Test=>engine speed low, manifold vac
high (throttle plate nearly closed, TPS output low). Low Voltage Test=>road/load speed>40
kph( >25mph), vacuum low(throttle plate open,TPS signal high). If improper TPS voltage,
code in 7sec.
POSSIBLE CAUSES
MAP SENSOR TROUBLE CODE PRESENT
TPS 5-VOLT SUPPLY CIRCUIT OPEN
TPS CONN & TERM CORR, DAM, PUSHED OUT OR MISWIRED
TPS HARNESS OR CONNECTORS INTERMITTENT DEFECT
TPS VOLTAGE ABOVE 1.0 VOLT
TPS VOLTAGE ABOVE 3.5 VOLTS
TPS VOLTAGE CHANGE NOT SMOOTH
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
Using the DRB, read trouble codes.
Is the9No Vehicle Speed Sensor Signal9trouble code present?All
Ye s®Refer to symptom P-0500 NO VEHICLE SPEED SENSOR SIG-
NAL in the DRIVEABILITY category.
No®Go To 2
2 Ignition On, Engine Not Running
Using the DRB read trouble codes.
Is a MAP Sensor trouble code present?All
Ye s®Refer to Symptom List for problems related to Driveability.
No®Go To 3
3 Ignition On, Engine Not Running
With the DRB read the MAP Sensor voltage.
Is MAP Sensor voltage below 3.5 volts?All
Ye s®Refer to symptom * CHECKING MAP SENSOR CALIBRATION
in the DRIVEABILITY category.
No®Go To 4
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TEST ACTION APPLICABILITY
4 Turn the ignition on.
With the DRB, read the FREEZE FRAME DATA.
Using the FREEZE FRAME DATA, attempt to duplicate the condition that has set
this fault.
While using the FREEZE FRAME DATA, pay particular attention to the fault setting
conditions, such as vehicle speed, engine temperature, vehicle load, and MAP
vacuum.
Does P0121 reset?All
Ye s®Go To 6
No®Go To 5
5 Ignition Off
Start engine.
With the DRB, read the MAP Sensor voltage.
Did the MAP Sensor voltage drop from above 3.5 volts to below 2.0 volts?All
Ye s®Go To 6
No®Refer to symptom * CHECKING MAP SENSOR CALIBRATION
in the DRIVEABILITY category.
6 Ignition On, Engine Not Running
Using the schematic as a guide, wiggle the TPS Harness and Connectors to PCM.
While monitoring the DRB, observe for the TPS voltage to change.
Did the TPS voltage change at any time?All
Ye s®Repair the Harness or Connectors as necessary.
Perform Powertrain Verification Test VER-5A.
No®Go To 7
7 Ignition On, Engine Not Running
With the DRB, read the Throttle Position Sensor voltage.
Is the Throttle Position Sensor voltage above 1.0 volt?All
Ye s®Replace the Throttle Position Sensor.
Perform Powertrain Verification Test VER-5A.
No®Go To 8
8 Ignition On, Engine Not Running
While monitoring the DRB, open the Throttle Plate to wide open throttle.
Is the Throttle Position Sensor voltage above 3.5 volts?All
Ye s®Go To 9
No®Replace the Throttle Position Sensor.
Perform Powertrain Verification Test VER-5A.
9 Ignition On, Engine Not Running
While monitoring the DRB slowly open and close the Throttle Plate.
Note: You must move linkage very slowly while looking for a jump in
voltage.
Is the voltage change smooth?All
Ye s®Go To 10
No®Replace the Throttle Position Sensor.
Perform Powertrain Verification Test VER-5A.
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P-0121 TPS VOLTAGE DOES NOT AGREE WITH MAP ÐContinued
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TEST ACTION APPLICABILITY
10 Ignition Off
Disconnect the Throttle Position Sensor.
Note: Check connectors - Clean/repair as necessary.
Ignition on, engine not running.
Using a Voltmeter, probe the 5-Volt Supply Circuit at the TP Sensor.
Is the voltage below 5.0 volts?All
Ye s®Repair the open 5-volt Supply Circuit to Throttle Position sensor.
Perform Powertrain Verification Test VER-5A.
No®Go To 11
11 Ignition Off
Check Throttle Plate and Linkage for a binding condition.
Ensure the Throttle Linkage is at the Idle Position.
Note: TPS Ground Circuit and the 5-Volt Supply Circuit switched will cause
this code to appear.
Disconnect the TP Sensor.
Inspect the TPS Wire colors for the correct cavities.
Note: Check connectors - Clean/repair as necessary.
Is any terminal damaged, pushed out, miswired or corroded?All
Ye s®Clean or repair Connector as necessary.
Perform Powertrain Verification Test VER-5A.
No®Test Complete.
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P-0121 TPS VOLTAGE DOES NOT AGREE WITH MAP ÐContinued
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Symptom:
P-0122 THROTTLE POSITION SENSOR VOLTAGE LOW
When Monitored and Set Condition:
P-0122 THROTTLE POSITION SENSOR VOLTAGE LOW
When Monitored: With the ignition on.
Set Condition: The TP sensor signal voltage goes below 0.16 volt.
POSSIBLE CAUSES
TPS 5-VOLT SUPPLY CIRCUIT OPEN
TPS SIGNAL CIRCUIT SHORT TO GROUND
TPS SIGNAL CIRCUIT SHORT TO SENSOR GROUND CIRCUIT
TPS WIRING HARNESS INTERMITTENT DEFECT
TPS WIRING HARNESS OBSERVABLE DEFECT
PCM DEFECTIVE (TPS)
THROTTLE POSITION SENSOR DEFECTIVE
THROTTLE POSITION SENSOR VOLTAGE CHANGE NOT SMOOTH
TRANSMISSION CONTROL MODULE DEFECTIVE (TPS)
TEST ACTION APPLICABILITY
1 Turn key on, engine off.
With the DRB, read the Throttle Position Sensor (TP Sensor) voltage.
Is the Throttle Position Sensor voltage below 0.16 volt?All
Ye s®Go To 2
No®Go To 8
2 Ignition Off
Disconnect the Throttle Position Sensor.
Note: Check connectors - Clean/repair as necessary.
Ignition On, Engine Not Running.
Measure the voltage at the 5-Volt Supply Circuit at TPS Connector.
Is the voltage below 4.0 volts?All
Ye s®Repair the open TP Sensor 5-Volt Supply Circuit.
Perform Powertrain Verification Test VER-5A.
No®Go To 3
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