Diagnostics Procedures
- Inspect the coolant system for proper level and condition.
Is the coolant level and condition OK?
- Yes --> Go To 2
- No --> Inspect the vehicle for a coolant leak and add the necessary amount of coolant.
Perform POWERTRAIN VERIFICATION TEST VER - 5 .
- Ignition on, engine not running.
With the DRBIII®, read the Eng Coolant Tmp Deg value. If the engine was allowed to sit overnight (cold soak), the temperature value should be a sensible value that is somewhere close to the ambient temperature.
Start the Engine.
During engine warm-up monitor the Eng Coolant Tmp Deg value. The temp deg value change should be a smooth transition from start up to normal operating temp 82°C (180°F). Also monitor the actual coolant temperature with a thermometer.
Using the appropriate service information, determine the proper opening temperature of the thermostat.
Did the thermostat open at the proper temperature?
- Yes --> Go To 3
- No --> Replace the thermostat.
Perform POWERTRAIN VERIFICATION TEST VER - 5 .
- Ignition on, engine not running.
With the DRBIII®, read the Eng Coolant Tmp Deg value. If the engine was allowed to sit overnight (cold soak), the temperature value should be a sensible value that is somewhere close to the ambient temperature.
NOTE: If engine coolant temperature is above 82°C (180°F), allow the engine to cool until 65°C (150°F) is reached.Start the Engine.
During engine warm-up monitor the Eng Coolant Tmp Deg value. The temp deg value change should be a smooth transition from start up to normal operating temp 82°C (180°F). Also monitor the actual coolant temperature with a thermometer.
NOTE: As the engine warms up to operating temperature, the actual coolant temperature (thermometer reading) and the Eng Coolant Tmp Deg in the DRB values should stay relatively close to each other.Is the thermometer reading relatively close to the DRBIII® ECT reading?
- Yes --> Test Complete.
- No --> Replace the Engine Coolant Temperature Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5 .