Diagnostic Aids

Check for the following conditions:

• If DTCs P0105, P0110, P0115, and P0120 are also set, the malfunction may be in a sensor ground circuit.
• If DTCs P0115 and P0116 are both set the ECT sensor circuit may be open or shorted. Perform the DTC P0115 diagnostic procedure first.
• Check for proper operation of engines cooling system, including correct coolant level.
• A faulty thermostat that stays open slightly can cause DTC P0116 to set in cold weather when vehicle is started and let sit while warming up. Replace any suspect thermostat.
• Use Temperature vs. Resistance table to evaluate the possibility of a shifted ECT sensor. A shifted sensor could result in DTC P0116. See TEMPERATURE VS. RESISTANCE  table.
• Check for a faulty electrical connection to PCM.

An intermittent malfunction may be caused by a fault in ECT sensor electrical circuit. Check wiring harness and components for an intermittent condition. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 1.8L VIBE article. Repair any electrical circuit faults that were found. If DTC P0116 cannot be duplicated, information included in freeze frame data can be useful in determining the vehicle operating conditions when the DTC was first set.