Autobox problems
I have a 2006 Ford Focus 1.6 automatic estate. The problem is with the autobox. In ‘Drive’, the car functions as normal, but it also has a ‘Tiptronic’ mode whereby the driver can change gear like a manual and this position does not function at all.
I have retrieved the fault codes ‘P0750’, ‘P0753’ and ‘P0960’, all relating to shift solenoid A. I have dropped the sump, removed and tested both the smaller solenoids – I believe the smaller one in the middle is solenoid A – but both were OK. To test them, I took a resistance reading off the solenoid with my ohmmeter, then using my ammeter as a jumper, I powered the solenoid with a known good battery. Using Ohm’s law, I calculated that the actual amp draw matched my calculation (ie, battery 11.5 volts, resistance 15 ohms).
My question is: can you provide me with a pin-out diagram for the gearbox ECU, showing each wire’s destination? I want to check power and ground for the ECU and also ensure that power is available for the solenoids, but my data source has little info on the gearbox.
Also, does this car have a gearbox ECU and a transmission shift module? If so, can you tell me its location?
Last, have you ever come across this or a similar problem before?
I mentioned that the car drove fine in ‘Drive’, so I am assuming that the actual gearbox is OK. The ATF fluid was murky, so I am in the process of flushing and refreshing it. Jonathan Dean According to my data, your vehicle has the four-speed, electronically-controlled gearbox fitted. As the Tiptronic control does not operate, I concur that the problem is electronic, as opposed to hydraulic. Having said that, I am not too happy about the murky fluid and would advise you to flush it through, as you are doing.
The vehicle does have a separate transmission control module (TCM), as well as the powertrain control module (PCM), and this is fitted on the bulkhead on the left-hand side. As this is the unit that controls the select or manual shift mode, this may be the problem.
The three codes all refer to circuit failure with the solenoid circuits, and I believe you are correct in wanting to trace the ECU wiring. I have forwarded a pin-out diagram for this purpose.
As the gearbox otherwise performs as it should, I would also consider the possibility of a problem with the shift control lever.