Fault Conditions

P1230

Throttle Position Sensor 1 And 2 Circuit. Sum Out Of Range.

(Faulty signal from throttle disc position sensor)







Fault symptoms
^ CHECK ENGINE.
^ Idling speed incorrect.
^ Starting problems, especially when engine is cold
^ Cruise control not working.

NOTE: Diagnosis has been improved in more recent software which means it is no longer necessary to change the throttle body. The software providing enhanced diagnosis is available for all model years and engine variants.

The throttle body must be reset mechanically following SPS programming (Service Programming System). If this is not done, other DTCs will be generated after several running cycles.

MY02 and later vehicles have this software. Perform regular fault diagnosis.

On-Board Diagnostics

Type of diagnosis:
^ Continuous. But interrupted when fault criteria fulfilled and will not restart until next driving cycle.

Enable criteria:
^ Ignition in ON position.

Fault criteria:
^ The sum of voltages from throttle position sensors 1 and 2 exceeds 5.70 V for more than 0.8 s or is less than 4.59 V for more than 0.3 s.

Dependents:
^ None.

System reaction to a fault:
^ Throttle control goes into limp-home mode. The limp-home solenoid will be activated 5 times in succession each time the ignition is turned on until the fault has been rectified and the trouble codes cleared.

OK report:
^ Accelerator pedal has been depressed at some time and then fully released. 120 s has expired since then without fault criteria being fulfilled.

Fault handling: (For more information refer to "Fault diagnosis, general". Description of On-Board Diagnostics)

^ CHECK ENGINE goes on immediately and can be turned off only by clearing the trouble codes.

Diagnostic help
Fault diagnosis relates to incorrect signals from the throttle disc position sensor and its wiring.

Functions in the diagnostic tool related to the fault:
^ Throttle Position Sensor 1, unit V.
^ Throttle Position Sensor 2, unit V.

For more information refer to description of read values, Menu Read Values

Checking the wiring
Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short circuits. Check switches, connectors and crimp connections for oxidation, withdrawn pins and pin clamping force.

Software table
Perform SPS programming (Service Programming System) if T7 has an earlier software version than that stated below. The software below has the updated diagnostic procedure for P1230.

Part 1:

Part 2:

Part 3: