P1231
Read the instructions below then
start the fault diagnostic procedure.
Symptom: Usually none, but the engine can be jerky at constant speeds or idle unevenly.
Throttle Position Sensor 1 and 2 Circuit. Sum Out of Range (No Limp Home).
Fault symptoms
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Usually none, but the engine
can
be jerky at constant speeds or idle unevenly.
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On-Board Diagnostics
Type of diagnosis:
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Continuous. But interrupted when fault criteria fulfilled and will not restart until next driving cycle.
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Enable criteria
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Ignition in ON position.
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Fault criteria
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The sum of voltages from throttle position sensors 1 and 2 exceeds 5.70 V for more than 320 ms.
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Dependents
System reaction to a fault
OK report
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Accelerator pedal has been depressed at some time and then fully released. 120 s has expired since then without fault criteria being fulfilled.
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Fault handling:
(See section x for more information.)
Diagnostic help
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A new DTC that is for information purposes only and indicates a minor disturbance in throttle control. This disturbance is harmless from a safety point of view. The DTC has been added to avoid the throttle body, ignition discharge module or other components being changed unnecessarily for this type of fault.
The DTC is generated by repeated, sporadic, very brief breaks in a throttle position sensor circuit. The DTC
does not
result in limp-home or Check Engine.
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Most often, such open circuits occur on potentiometer 2. These open circuits do not affect the running of the engine.
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In some cases, there can be an open circuit on potentiometer 1. The throttle will then briefly move towards its closed position. Uneven idling may be noticed or jerkiness while driving, especially if the same pedal position has been maintained for a long period of time. Ask the customer about the degree of such irregularities when considering whether the throttle body needs to be changed.
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