DTC Troubleshooting: P0116 (86)
DTC P0116:
 ECT Sensor 1 Range/Performance Problem
NOTE: Before you troubleshoot, record all freeze data and review the general troubleshooting information.
  1. Turn the ignition switch ON (II).
  1. Check the ECT SENSOR 1 in the DATA LIST with the HDS.
Is about 80 °C (176 °F) or higher or less indicated?
YES -
Go to Step 3 .
NO -
Go to Step 7 .
  1. Note the current coolant temperature.
  1. Turn the ignition switch OFF.
  1. Cool the engine for 1 hour.
  1. Check the ECT SENSOR 1 in the DATA LIST with the HDS.
Does the ECT change 2 °C (3.6 °F) or more?
YES -
Intermittent failure, the system is OK at this time. Check the thermostat and the cooling system.■
NO -
Go to Step 10 .
  1. Note the current coolant temperature.
  1. Start the engine. Hold the engine speed at 2,000 rpm (min −1 ) without load (in neutral) until the radiator fan comes on, then let it idle.
  1. Check the ECT SENSOR 1 in the DATA LIST with the HDS.
Does the ECT change 2 °C (3.6 °F) or more?
YES -
Intermittent failure, the system is OK at this time. Check the thermostat and the cooling system.■
NO -
Go to Step 10 .
  1. Turn the ignition switch OFF.
  1. Cool the engine for 1 hour.
  1. Turn the ignition switch ON (II).
  1. Reset the ECM with the HDS.
  1. Start the engine. Hold the engine speed at 2,000 rpm (min −1 ) without load (in neutral) until the radiator fan comes on, then let it idle 20 minutes.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0116 indicated?
YES -
Check for poor connections or loose terminals at ECT sensor 1 and the ECM, then go to Step 1 .
NO -
Go to Step 17 .
  1. Monitor the OBD STATUS for DTC P0116 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
Troubleshooting is complete. If any other Temporary DTCs or DTCs were indicated, in Step 16 , go to the indicated DTC's troubleshooting.■
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at ECT sensor 1 and the ECM, then go to Step 1 . If the screen indicates NOT COMPLETED, go to Step 15 .