| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. | 
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. | 
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category | 
Circuit  | Short to Ground  | High Resistance  | Open  | Short to Voltage  | Signal Performance  | 
|---|---|---|---|---|---|
EOT Sensor Signal  | P0198  | P0196, P0197  | P0197  | P0197  | P0196  | 
EOT Low Reference  | --  | P0196, P0197  | P0197  | --  | P0196  | 
The Engine Oil Temperature (EOT) Sensor is a variable resistor that measures the temperature of the engine oil. The engine control module (ECM) supplies a 5 voltage to the EOT signal circuit and supplies a ground for the reference circuit.
| • | The engine speed is greater than 25 RPM. | 
| • | The engine oil temperature EOT is between -35 to +170°C (-31 to +338°F). | 
| • | The DTC runs continuously when the above enable conditions are met for greater than 10 seconds. | 
| • | The ignition is ON, or the engine is operating. | 
| • | The DTCs runs continuously when the above enable condition is met for greater than 2 seconds. | 
The ECM detects the actual EOT is 40°C (104°F) colder than the calculated EOT of the controller, for greater than 4 seconds or a cumulative time of 30 seconds.
The ECM detects the EOT is colder than -35°C (-31°F) for greater than 4 seconds or a cumulative time of 30 seconds.
The ECM detects the EOT is warmer than 170°C (331°F) for greater than 4 seconds or a cumulative time of 30 seconds.
DTCs P0196, P0197 and P0198 are type B DTCs.
DTCs P0196, P0197 and P0198 are type B DTCs.
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. | 
| ⇒ | If greater than the specified range, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the ECM. | 
Note: If the fuse in the jumper wire opens, the signal circuit is shorted to a voltage and the sensor may be damaged.
| ⇒ | If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance, if the circuit tests normal, replace the ECM. | 
Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Engine Control Module Replacement for ECM replacement, setup, and programming