P0116
Read the instructions below then
start the fault diagnostic procedure.
Symptom: CHECK ENGINE.
A/C not working.
Radiator fan running continuously when ignition in position ON.
Temperature gauge reading incorrect.
Possible misfiring before diagnostic trouble code is generated.
Engine Coolant Temperature Circuit. Performance Problem.
Fault symptoms
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Radiator fan running continuously when ignition in position ON.
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Temperature gauge reading incorrect.
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Possible misfiring before diagnostic trouble code is generated.
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On-Board Diagnostics
Type of diagnosis:
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Test 1: Continuous. However, it is interrupted once the fault criteria have been fulfilled and does not restart until the next driving cycle.
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Tests 2 and 3: Once per driving cycle. It is interrupted once fault criteria have been fulfilled or OK has been reported. Restarts next driving cycle.
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Enable criteria:
(Conditions that must be fulfilled for diagnostics to be performed.)
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Global conditions for this diagnostic trouble code: When starting the engine, the atmospheric pressure must exceed 78 kPa and the temperature of the coolant and the intake air must exceed -7°C.
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Test 1: Engine running.
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Test 2: Engine running. A counter accumulates the length of time during which the mass air flow has exceeded 10 g/s. The counter has reached 400 s.
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Test 3: Engine has started. A substitute value for the coolant temperature is calculated: Intake air temperature at start is incremented by 1°C per 60 g air mass/s.
A counter accumulates the length of time during which the mass air flow has exceeded 10 g/s. After 350s., an intake temperature-dependent maximum value is set as the substitute value (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 corresponds as closely as possible to the outer temperature.
After 400s., the sensor value is compared with the substitute value.
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Fault criteria:
(When enable criteria have been fulfilled, diagnostics will check if the fault criteria have been fulfilled.)
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Test 1: The sensor value changes more than 10°C/s.
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Test 2: The sensor value has changed less than 1°C.
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Test 3: The sensor value is more than 20°C below the substitute value or exceeds the substitute value by more than 48°C.
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Dependents:
(Once fault criteria have been fulfilled, a number of other diagnostics must report OK before the diagnostic trouble code can finally be generated.)
System reaction to a fault:
(Once the fault criteria have been fulfilled, certain measures will sometimes be taken.)
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A substitute value is calculated continuously as follows: Intake air temperature at start is incremented by 1°C per 60g air mass/s. The value is maximized to 90°C and is used as soon as the fault criteria for the sensor have been fulfilled.
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OK report:
(This diagnosis may be included as a dependent to another diagnosis and must therefore report OK even if it is continuous. The OK report is also used in fault handling to count down the fault counter.)
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Test 2 and Test 3 performed once and fault criteria not fulfilled. Fault criteria for Test 1 not fulfilled. Fault criteria for P0117 or P0118 not fulfilled.
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Fault handling:
(Refer to section “Fault diagnosis, general” for more information.)
Diagnostic help
Fault diagnosis concerns an electrical fault in the connecting leads or in the sensor.
Diagnostic tool functions related to this fault:
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Diagnostic status for the diagnosis.
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Temperature sensor reading, unit °C.
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Refer also to the description of readings under ”Fault diagnosis, general” for more information
Check the wiring
Jiggle the wiring harness at several points and in different directions to check if there are intermittent breaks and short-circuits in the leads. Observe the multimeter, test lamp or diagnostic instrument during the test.
