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 DTC P0118 [L8, LF, L3]

DTC P0118 [L8, LF, L3]

id0102a1804100

DTC P0118

ECT sensor circuit high input

DETECTION CONDITION

• The PCM monitors the ECT sensor signal. If the PCM detects that the ECT sensor voltage is above 4.6 V, the PCM determines that the ECT sensor circuit has a malfunction.
Diagnostic support note
• This is a continuous monitor (Engine cooling system).
• The MIL illuminates if the PCM detects the above malfunction condition during first drive cycle.
• PENDING CODE is available if the PCM detects the above malfunction condition.
• FREEZE FRAME DATA is available.
• Are any DTCs is stored in the PCM memory.

POSSIBLE CAUSE

• ECT sensor malfunction
• Open circuit in wiring harness between ECT sensor terminal A and PCM terminal 2AH
• Short to power supply in wiring harness between ECT sensor terminal A and PCM terminal 2AH
• Open circuit in wiring harness between ECT sensor terminal B and PCM terminal 2AY
• Poor connection of ECT sensor or PCM connectors
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related Service Information availability.
• Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service information.
If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT ECT SENSOR CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch off.
• Disconnect ECT sensor connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 9.
No
Go to the next step.
4
CLASSIFY ECT SENSOR MALFUNCTION OR WIRING HARNESS MALFUNCTION
• Connect the WDS or equivalent to the DLC-2.
• Access ECT PID.
• Connect a jumper wire between ECT sensor terminals A and B.
• Verify the ECT value.
• Is the voltage 4.6 V or below?
Yes
Replace the ECT sensor, then go to Step 9.
No
Go to the next step.
5
INSPECT ECT SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER
• Turn the ignition switch to the ON position (Engine off).
• Measure the voltage between ECT sensor terminal A (wiring harness-side) and body ground.
• Is the voltage B+?
Yes
Repair or replace the wiring harness for short to power supply, then go to Step 9.
No
Go to the next step.
6
INSPECT PCM CONNECTOR FOR POOR CONNECTION
• Disconnect the PCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 9.
No
Go to the next step.
7
INSPECT ECT SENSOR SIGNAL CIRCUIT FOR OPEN CIRCUIT
• Inspect for continuity between ECT sensor terminal A (wiring harness-side) and PCM terminal 2AH.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit, then go to Step 9.
8
INSPECT ECT SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
• Inspect for continuity between ECT sensor terminal B (wiring harness-side) and PCM terminal 2AY.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit, then go to the next step.
9
VERIFY TROUBLESHOOTING OF DTC P0118 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Perform the KOEO or KOER self-test.
• Is the DTC P0118 present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
10
VERIFY AFTER REPAIR PROCEDURE
• Perform the "After Repair Procedure".
• Are any DTC present?
Yes
Go to the applicable DTC troubleshooting.
No
Troubleshooting completed.