Fault Conditions

PO116

Engine Coolant Temperature Circuit. Performance Problem.












Fault Symptoms
- CHECK ENGINE.
- A/C malfunctioning.
- Radiator fan running continuously when ignition is ON.
- Temperature gauge displaying incorrect value.
- Misfiring can occur before trouble code is generated.

On-Board Diagnostics

Type of diagnosis:
- Test 1 and 2: Once per driving cycle. Interrupted when fault criteria fulfilled or OK reported. Restarts next driving cycle.

Enable criteria:
- General conditions for this trouble code: Atmospheric pressure must exceed 72 kPa and the engine coolant and intake air temperatures must exceed -7°C.
- Test 1: Engine running. A counter accumulates the time during which the mass air flow has exceeded 10 g/s. Counter has reached 400 s.
- Test 2: Engine running. A substitute value is calculated for the engine coolant temperature: the starting intake air temperature is intermitten with 1°C per 60 g air mass/s. A counter accumulates the time during which the air mass flow has exceeded 10 mg/s. An maximum is set for the substitute value after 350 s that is dependent on the intake air temperature (normally 65-80°C). The maximum value is set as soon as the air mass/combustion is not too high and the air mass/s is not too low, so that the intake air temperature will be as close as possible to the outdoor temperature. After 400 s, the sensor value will be compared with the substitute value.

Fault criteria:
- Test 1: Sensor value has changed less than 1°C.