TEST
ACTION
APPLICABILITY
1
NOTE: If multiple DTCs are present, the most likely cause is a 5-Volt Supply
or Sensor Ground circuit shorted to voltage or ground. Refer to the Service
Information Wiring section for circuits that would affect multiple DTCs.
NOTE: If the ECM detects and stores a DTC, the ECM also stores the
engine/vehicle operating conditions under which the DTC was set. Some of
these conditions are displayed on the DRB at the same time the DTC is
displayed.
NOTE: Before erasing stored DTCs, record these conditions. Attempting to
duplicate these conditions may assist when checking for an active DTC.
Turn the ignition on.
With the DRB, monitor the Engine Coolant Temperature (ECT) Sensor voltage.
Is the ECT Sensor voltage above 4.90 volts?
All
Yes
→ Go To 2
No
→ Go To 7
2
Turn the ignition off.
Disconnect the ECT Sensor harness connector.
Turn the ignition on.
Measure the voltage on the ECT Sensor Signal circuit.
Is the voltage above 5.5 volts?
All
Yes
→ Repair the ECT Sensor Signal circuit for a short to voltage.
Perform ROAD TEST VERIFICATION - VER-2.
No
→ Go To 3
3
Turn the ignition off.
Disconnect the ECT Sensor harness connector.
Connect a jumper wire between the ECT Sensor harness connector cavities.
Turn the ignition on.
With the DRB, read the ECT Sensor voltage.
Is the voltage below 1.0 volt?
All
Yes
→ Replace the ECT Sensor in accordance with the Service Informa-
tion.
Perform ROAD TEST VERIFICATION - VER-2.
No
→ Go To 4
4
Turn the ignition off.
Disconnect the ECT Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance of the ECT Sensor Ground circuit.
Is the resistance below 10.0 ohms?
All
Yes
→ Go To 5
No
→ Repair the ECT Sensor Ground circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
5
Turn the ignition off.
Disconnect the ECM harness connectors.
Disconnect the ECT Sensor harness connector.
Measure the resistance of the ECT Sensor Signal circuit.
Is the resistance below 10.0 ohms?
All
Yes
→ Go To 6
No
→ Repair the ECT Sensor Signal circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
45
DRIVEABILITY - DIESEL
P0115-ENGINE COOLANT TEMP SENSOR CIRCUIT SIGNAL VOLTAGE
TOO HIGH —
Continued