P1230

P1230 - Throttle Position Sensor 1 and 2 Circuit. Sum Out of Range.
(Incorrect signal from throttle disc position sensor)






Fault symptom:
- CHECK ENGINE.
- Idling speed incorrect.
- Starting difficulties, especially when the engine is cold
- Cruise control not working.

Note:
Diagnosis has been improved in recent software, so it is not necessary to replace the throttle body. Software with improved diagnosis is available for all model years and engine variants.

The throttle body must be reset manually after SPS (Service Programming System) or other DTCs will appear after a few driving cycles.


Procedure
For cars before model year -02:

1. Check the software. Is the control module equipped with software earlier than that listed in the "software table"? (see farther down on this page)
YES: see point 2
NO: see point 3

2. Carry out SPS (Service Programming System)
NOTE: The throttle body is not to be replaced.
2.1. Reset the limp-home mechanism. See "Reset of triggered limp-home solenoid"
2.2. Road test the car.
2.3. Read out the DTCs.
2.4. Does the DTC recur?
YES: see point 3
NO: correct procedure was performed.

3. Follow ordinary fault diagnosis.


On-board diagnosis:

Type of diagnosis:

- Continuous, but interrupted when fault criteria are fulfilled and will not restart until next driving cycle.

Enable criteria:
- Ignition in ON position.

Fault criteria:
- The sum of the voltages from throttle position sensor 1 and 2 exceeds 5.70 V for more than 0.8 sec or falls below 4.59 V for more than 0.3 sec.

Dependencies:
- None.

System reactions to fault:
- Throttle control is set to limp-home. The limp-home solenoid is activated 5 times in sequence during each ignition until the fault is remedied and the DTCs are cleared.

OK report:
- The accelerator pedal was depressed at some point and then completely released. 120 sec have since elapsed without fault criteria being fulfilled.

Fault handling: (See section Fault diagnosis, general for more information.)
- CHECK ENGINE goes on immediately and can be turned off only by clearing the trouble codes.


Diagnostic help:

The diagnosis regards an incorrect signal from the throttle disc position sensor and its connecting leads.

Functions of the diagnostic tool related to the fault:
- Throttle position sensor 1, unit V.
- Throttle position sensor 2, unit V.

See also the description of read values under "Read Values" menu for more information.

Wiring harness check:

Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short circuits. In addition, check contacts, connectors and crimp connections for oxidation, dislodged pins and pin clamping force.

Software table:

Carry out SPS (Service Programming System) if T7 has an earlier software version than those listed below. The software below has the updated diagnosis for P1230.