Cvt Fault Facts Request.

[Pavillion]

I and some other souls have a more technical interest in the Ford CFT23 gearbox and its failures. At the risk of being a complete fool, I believe that some of the apparent terminal breakdowns are not necessarily so, however as Ford stonewalls as far as this gearbox is concerned there is no definitive explanation as to what goes wrong inside.

I have therefore decided to start this topic to try and collate what facts exist. If you have had a failure, or had a gearbox temporarily showing a problem, could I ask you here to post what you know. I am especially interested in Diagnostic Trouble Codes (DTCs).

May I be bold and ask that contributor do not post what happened to them, but stick to facts, i.e. fault codes or what the dealer or specialist has actually told you what had gone wrong. I am wary of collating the failure experiences as one person’s interpretation or explanation may be very different from another person’s.

If enough people post DTCs, it may be that we can have an educated guess as to what has gone wrong, and whether a fix is possible. I do not want to get peoples’ hopes up as we the general public do not have Ford’s insight and database to use. Whilst none of this will necessarily help those who have already suffered failure it might help those in the future.

Thank you,

Pavillion.

[john R]

Hi This is John R.

I have a c-max with an intermittent cvt problem. 2005 1.6 CVT

It only occures when the car is standing still, traffic lights, etc. then the "transmission Malfunction" message appears. Turning off the engine and restarting, clear the message and the car operates correctly until the next time. It is intermittent with no pattern to when it will occure again.

The fauts codes set are:

P0701 TRANS CONTROL SYSTEM RANGE.

P0961 PRESSURE CONTROL SOLINOID A CONTROL CIRCUIT

P0871 TRANS FLUID PRESSURE SENSOR/SWITCH "C"

If i keep the rpm slightly above idle the problem is less likely to occur!

It appears that the oil pressure maybe dropping below the required level when idling. Keeping the idle speed up helps to reduce this.

I've worked in a motor companies (Volvo)technical dept for many years before retiring. So have some technical knowledge of how things work.

Ive changed the oil and check the basic electrical connections to the CVT unit.

Sorry for expanding more than just the codes, but some back ground might be useful.

Happy to dicuss in more detail if required.

Regards John R.

I and some other souls have a more technical interest in the Ford CFT23 gearbox and its failures. At the risk of being a complete fool, I believe that some of the apparent terminal breakdowns are not necessarily so, however as Ford stonewalls as far as this gearbox is concerned there is no definitive explanation as to what goes wrong inside.

I have therefore decided to start this topic to try and collate what facts exist. If you have had a failure, or had a gearbox temporarily showing a problem, could I ask you here to post what you know. I am especially interested in Diagnostic Trouble Codes (DTCs).

May I be bold and ask that contributor do not post what happened to them, but stick to facts, i.e. fault codes or what the dealer or specialist has actually told you what had gone wrong. I am wary of collating the failure experiences as one person’s interpretation or explanation may be very different from another person’s.

If enough people post DTCs, it may be that we can have an educated guess as to what has gone wrong, and whether a fix is possible. I do not want to get peoples’ hopes up as we the general public do not have Ford’s insight and database to use. Whilst none of this will necessarily help those who have already suffered failure it might help those in the future.

Thank you,

Pavillion.

[john R]

Hi Thanks for your reply to me, for some reason i can't follow the link to answer you direct. So I'm happy to add the answer here.

When I changed the oil, I did remove the sump, and change the filer, and clean everthing. With the sump off i checked the electrical connection to the CVT unit, all looked in good condition.

Below the ======= is a slightly longer version of the problem.

I've covered approx 10,000 miles since this started, about a week after buying the damn thing! (smile) and it does not appear to have developed. So it's about the same now as it was!

I do find that by holding the engine RPM slightly high when at a standstill(traffic lights) definatly helps. This indicates that the CVT unit oil pressure is dropping below a value, the oil pressure sensor see's this and sets the codes. sadly the new correct from Ford oil did not help or change my problem.

I hope this helps, and more than happy to help if i can. If anything changes I will update the post.

Sorry for going on abit, hope it helps.

Best regards John

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FORD C-MAX

2005 MY

SA05DPE

Mileage, 659889

The car has a very intermittent problem.

Under normal driving the car and transmission works well. However, when coming to a stand still, very intermittently, the Transmission Malfunction warning message comes up on the dash. If you try to pull away, there is a delay, and it’s as if you are starting off in 2nd gear. Also the gear selector lever goes stiffer than normal, with it very difficult to select another gear (Reverse)

However, by turning off the engine and restarting, the fault message is deleted and the transmission works correctly.

There are no factors I can see that triggers this, Temp, weather condition, speed, duration of journey, etc! apart from the car coming to a standstill for a few seconds.

There were 3 fault codes set in the Transmission Control Module,

P0701, Transmission Control System Range/Performance.

P0961, Pressure control Solenoid “A” control circuit Range/Performance.

P0871, Transmission Fluid Pressure Sensor Switch “C” Circuit Range /Performance.

The way the car reacts when the codes are set, indicates the system going in to "limp" mode. So the "fault" could only last a few milliseconds, but it's the Limp mode is what you experience!

I have changed the transmission fluid and filter in the Trans sump.