Ford Focus 2.0 Diesel - Cruise Control Problem

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Thu 2 May 2013 15:28
Ford Focus 2.0 Diesel - Cruise Control Problem - Pbar

I have a focus 2.0 diesel (Dec 2005) which has developed an intermittent fault causing the cruise control to stop working. The cruise control fault is preceded by an ‘Engine Systems Fault’ warning message for a few seconds.

The problem occurs on most journeys. I have noticed that the fault often occurs when steering to the left and when I press the decrease speed button on the cruise control. The cruise control works properly up to the point when the warning message shows, thereafter it will not activate, until re-starting the engine.

A local service garage identified fault codes P0579 and P0581 but advised that only a Ford dealer would be able to take the diagnostics further.

I am wondering if there is a sensor on the steering which deactivates the cruise control at a certain turn radius which is faulty.

Any thoughts would be really appreciated.

Thanks Pbar

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Thu 2 May 2013 23:01
Ford Focus 2.0 Diesel - Cruise Control Problem - MikeTorque

P0579 Cruise Control Multi-Function Input "A" Circuit Range/Performance
Possible causes
- Faulty Cruise Control Multifunction Switch
- Cruise Control Multifunction Switch harness is open or shorted
- Cruise Control Multifunction Switch circuit poor electrical connection

Symptoms - Engine Light ON (or Service Engine Soon Warning Light)
- Cruise control system inoperative

The ECM has detected a multifunction switch A input error.

P0581 Cruise Control Multi-Function Input "A" Circuit High
Possible causes
- Faulty Cruise Control Multifunction Switch
- Cruise Control Multifunction Switch harness is open or shorted
- Cruise Control Multifunction Switch circuit poor electrical connection

Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Cruise control system inoperative

A Ford garage will be able to run live diagnostics (Ford specialist equipment) to help ascertain the exact cause of the cruise control problem.

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Fri 3 May 2013 10:37
Ford Focus 2.0 Diesel - Cruise Control Problem - Pbar

Many thanks for quick response.

If it is the cruise mutifunction switch, would that explain why the 'Engine System Warnig' light comes on when turning the steering wheel to the left? This occurs irrespective of the cruise control being on or off.

Thank you.

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Fri 3 May 2013 13:51
Ford Focus 2.0 Diesel - Cruise Control Problem - MikeTorque

Yes most likely.

The Ford live diagnostics equipment is able to find error codes in addition to the static codes generated by general code readers, they will be able to confirm the exact trigger of the Engine System light.

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