DTC Troubleshooting: P0118
DTC P0118: ECT Sensor 1 Circuit High Voltage
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.

DTC Description
Confirmed DTC
Pending DTC
Freeze Frame
P0118 ECT Sensor 1 Circuit High Voltage
     

1.
Problem verification:

Problem verification
?1.
Press the engine start/stop button to select the ON mode.

?2.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
ECT SENSOR 1
More than 4.92
V
    

Do the current condition(s) match the threshold?

     
YES
     
     
     
The failure is duplicated. Go to step 2.
     
NO
     
     
     
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at ECT sensor 1 and the PCM.?
2.
ECT sensor 1 check:

ECT sensor 1 check
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Connect terminals A and B with a jumper wire.
Terminal A
ECT sensor 1 2P connector No. 1 (GRY)
Terminal B
ECT sensor 1 2P connector No. 2 (PNK)


?4.
Press the engine start/stop button to select the ON mode.

?5.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
ECT SENSOR 1
More than 4.92
V
    

Do the current condition(s) match the threshold?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
3.
Determine possible failure area (TW line, SG2 line):

Determine possible failure area (TW line, SG2 line)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Remove the jumper wire.

?3.
Press the engine start/stop button to select the ON mode.

?4.
Measure the voltage between test points 1 and 2.
Test condition
ON mode
 
ECT sensor 1 2P connector: disconnected
Test circuit
TW
Test point 1
ECT sensor 1 2P connector No. 2 (PNK)
Test point 2
Body ground


Is there about 5.0 V?

     
YES
     
     
     
Go to step 4.
     
NO
     
     
     
Go to step 5.
4.
Open wire check (SG2 line):

Open wire check (SG2 line)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Jump the SCS line with the HDS.


?3.
Disconnect the following connector.

?4.
Check for continuity between test points 1 and 2.
Test condition
OFF mode
 
ECT sensor 1 2P connector: disconnected
 
PCM connector B (51P): disconnected
Test circuit
SG2
Test point 1
ECT sensor 1 2P connector No. 1 (GRY)
Test point 2
PCM connector B (51P) No. 45 (GRY)


Is there continuity?

     
YES
     
     
     
The SG2 wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM, then do the repair verification.
     
NO
     
     
     
Repair an open in the SG2 wire between the PCM (B45) and ECT sensor 1, then do the repair verification.
5.
Open wire check (TW line):

Open wire check (TW line)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Jump the SCS line with the HDS.


?3.
Disconnect the following connector.

?4.
Check for continuity between test points 1 and 2.
Test condition
OFF mode
 
ECT sensor 1 2P connector: disconnected
 
PCM connector C (51P): disconnected
Test circuit
TW
Test point 1
ECT sensor 1 2P connector No. 2 (PNK)
Test point 2
PCM connector C (51P) No. 48 (PNK)


Is there continuity?

     
YES
     
     
     
The TW wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM, then do the repair verification.
     
NO
     
     
     
Repair an open in the TW wire between the PCM (C48) and ECT sensor 1, then do the repair verification.
Repair verification:

?1.
Press the engine start/stop button to select the OFF mode.

?2.
Reconnect all connectors.

?3.
Exit the SCS mode with the HDS.


?4.
Press the engine start/stop button to select the ON mode.

?5.
Reset the PCM with the HDS.


?6.
Do the PCM idle learn procedure.

?7.
Check for Pending or Confirmed DTCs with the HDS.
DTC Description
Confirmed DTC
Pending DTC
Freeze Frame
P0118 ECT Sensor 1 Circuit High Voltage
     


Is DTC P0118 indicated?

     
YES
     
     
     
Check for poor connections or loose terminals at ECT sensor 1 and the PCM. If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1.
     
NO
     
     
     
Troubleshooting is complete. If the PCM was substituted, replace the original PCM. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.?