Selespeed fault p2905

[guy200]

Hello everybody,

Please excuse my English. It's not my native language...

I have a Selespeed issue and I hope you can help me identify the problem.

My car is Alfa 159 2.2 JTS (2011).

Occasionally the gearbox is going crazy when changing gear (in auto mode, much less if any in manual mode).

I run AlfaOBD software for faults reading and got a diagnostic report for the Automatic gearbox Marelli SELESPEED CFC300 module.

The fault that was found is p2905 (Gearbox sub-system Incorrect engagement/selection). I attached the full report below.

What do you think is the faulty component? Any help would be appreciated.

Thanks,
Guy.

___________________________
Reading faults for: Automatic gearbox Marelli SELESPEED CFC300
___________________
Faults reported:
14/12/2018 08:34:02.851
Faults found.
P2905
Error code: P2905
Gearbox sub-system
Incorrect engagement/selection
Failure lamp not requested
Fault intermittent
Test complete or not applicable
Minutes: 39
Engine RPM: 864
Car speed: 4.23 km/h
Gear requested: Second
Gear engaged: Second
Hydraulic circuit pressure: 39.00 bar
Engine RPM: 864 rpm
Car speed: 4.23 km/h
Gear requested: Second
Gear engaged: Second
Gearbox Oil Temperature: 35.20 °C
Battery voltage: 12.59 V
Error counter: 35
___________________________
Reading faults for: Automatic gearbox Marelli SELESPEED CFC300
___________________
Faults reported:
14/12/2018 08:34:40.481
Faults found.
P2905
Error code: P2905
Gearbox sub-system
Incorrect engagement/selection
Failure lamp not requested
Fault intermittent
Test complete or not applicable
Minutes: 39
Engine RPM: 864
Car speed: 4.23 km/h
Gear requested: Second
Gear engaged: Second
Hydraulic circuit pressure: 39.00 bar
Engine RPM: 864 rpm
Car speed: 4.23 km/h
Gear requested: Second
Gear engaged: Second
Gearbox Oil Temperature: 35.20 °C
Battery voltage: 12.59 V
Error counter: 35
___________________________
Tested device: Automatic gearbox Marelli SELESPEED CFC300
___________________
14/12/2018 08:35:32.922
DEVICE INFO:
Fiat drawing number: 51835836
Hardware number: CFC 300F.02
Hardware version: 00
Software number: AHA26YBM
Software version: 0000
Homologation number:
ISO code: BC070D86AB
Programming date: 10/11/2008
__________________________
Gear lever position: Neutral requested from lever
Request from steering wheel levers: No request
Engine startup: Not requested
Key signal: Present
Brake pedal from CAN: Released
Brake pedal: Released
Driver door: Open
Automatic request: Released
ECO/SPORT request: Released
Solenoid valve selection: Not active
Lever release solenoid command: On
Pump relay: Off
Acoustic indicator: Off
Start-up enable relay: Off
Speed requested: Neutral
Neutral secure engagement threshold: 34.75 mm
First gear secure engagement threshold: 19.65 mm
Second gear secure engagement threshold: 40.95 mm
Third gear secure engagement threshold: 19.12 mm
Fourth gear secure engagement threshold: 41.60 mm
Fifth gear secure engagement threshold: 19.59 mm
Sixth gear secure engagement threshold: 41.00 mm
Reverse secure engagement threshold: 19.35 mm
Neutral engagement threshold valve ON: 35.75 mm
1st engagement threshold valve ON: 18.29 mm
2nd engagement threshold valve ON: 41.95 mm
3rd engagement threshold valve ON: 17.76 mm
4th engagement threshold valve ON: 42.60 mm
5th engagement threshold valve ON: 18.23 mm
6th engagement threshold valve ON: 42.01 mm
Reverse engagement threshold valve ON: 17.99 mm
Neutral/reverse selection threshold: 89.47 mm
1st/2nd selection threshold: 112.11 mm
3rd/4th selection threshold: 134.31 mm
5th/6th selection threshold: 158.06 mm
Clutch degradation index: 3420
Pump ON time: 1166 min
System ON time: 178037 min
Clutch over temperature time: 94 sec
Clutch over speed counter: 0
Out of engagement counter: 0
Counter � Unwanted Clutch Closing Started: 0
Clutch incorrect closure counter: 0
Gearbox/clutch self-calibration: Not performed
Oil leaks on electrovalve in the OFF: 1.80 cc/min
Oil leaks on electrovalve in the ON: 1.80 cc/min
Total speed changes counter: 678796
Engagement errors counter: 255
Incorrect selections errors counter: 3
Blocked selections error counter: 4
Counter errors paddles switch stuck: 3
LEVER switch blocked error counter: 8
AUTO switch blocked error counter: 0
Counter errors switch ECO/SPORT stuck: 0
Blocked pump relay error counter: 0
Low pressure errors counter: 0
Pump error counter: 0
Counter of pump temperature errors: 0
Incorrect uses counter: 0
Number of self-calibrations OK counter: 4
Brake node (NFR): Learnt
Degradation index fast calibrations counter: 153
Clutch open failure errors counter: 1
Clutch hookup point: Performed
Degradation index calculation: Performed
Clutch SV stabilized current: Calculated
Grid threshold storage result: OK
Grid thresholds storage: Performed
Grid plausibility: OK
__________________________
Gear lever position: Neutral requested from lever
Request from steering wheel levers: No request
Engine startup: Not requested
Key signal: Present
Brake pedal from CAN: Pressed
Brake pedal: Pressed
Driver door: Open
Automatic request: Released
ECO/SPORT request: Released
Solenoid valve selection: Not active
Lever release solenoid command: Off
Pump relay: Off
Acoustic indicator: Off
Start-up enable relay: Off
Speed requested: Neutral
Neutral secure engagement threshold: 34.75 mm
First gear secure engagement threshold: 19.65 mm
Second gear secure engagement threshold: 40.95 mm
Third gear secure engagement threshold: 19.12 mm
Fourth gear secure engagement threshold: 41.60 mm
Fifth gear secure engagement threshold: 19.59 mm
Sixth gear secure engagement threshold: 41.00 mm
Reverse secure engagement threshold: 19.35 mm
Neutral engagement threshold valve ON: 35.75 mm
1st engagement threshold valve ON: 18.29 mm
2nd engagement threshold valve ON: 41.95 mm
3rd engagement threshold valve ON: 17.76 mm
4th engagement threshold valve ON: 42.60 mm
5th engagement threshold valve ON: 18.23 mm
6th engagement threshold valve ON: 42.01 mm
Reverse engagement threshold valve ON: 17.99 mm
Neutral/reverse selection threshold: 89.47 mm
1st/2nd selection threshold: 112.11 mm
3rd/4th selection threshold: 134.31 mm
5th/6th selection threshold: 158.06 mm
Clutch degradation index: 3420
Pump ON time: 1166 min
System ON time: 178037 min
Clutch over temperature time: 94 sec
Clutch over speed counter: 0
Out of engagement counter: 0
Gear lever position: Neutral requested from lever
Request from steering wheel levers: No request
Engine startup: Not requested
Key signal: Present
Brake pedal from CAN: Released
Brake pedal: Released
Driver door: Open
Automatic request: Released
ECO/SPORT request: Released
Solenoid valve selection: Not active
Lever release solenoid command: On
Pump relay: Off
Acoustic indicator: Off
Start-up enable relay: Off
Speed requested: Neutral
Neutral secure engagement threshold: 34.75 mm
First gear secure engagement threshold: 19.65 mm
Second gear secure engagement threshold: 40.95 mm
Third gear secure engagement threshold: 19.12 mm
Fourth gear secure engagement threshold: 41.60 mm
Fifth gear secure engagement threshold: 19.59 mm
Sixth gear secure engagement threshold: 41.00 mm
Reverse secure engagement threshold: 19.35 mm
Neutral engagement threshold valve ON: 35.75 mm
1st engagement threshold valve ON: 18.29 mm
2nd engagement threshold valve ON: 41.95 mm
3rd engagement threshold valve ON: 17.76 mm
4th engagement threshold valve ON: 42.60 mm
5th engagement threshold valve ON: 18.23 mm
6th engagement threshold valve ON: 42.01 mm
Reverse engagement threshold valve ON: 17.99 mm
Neutral/reverse selection threshold: 89.47 mm
1st/2nd selection threshold: 112.11 mm
3rd/4th selection threshold: 134.31 mm
5th/6th selection threshold: 158.06 mm
Clutch degradation index: 3420
Pump ON time: 1166 min
System ON time: 178037 min
Clutch over temperature time: 94 sec
Clutch over speed counter: 0
Out of engagement counter: 0
Counter � Unwanted Clutch Closing Started: 0
Clutch incorrect closure counter: 0
Incorrect engagement/selection
Failure lamp not requested
Fault intermittent
Test complete or not applicable
Minutes: 39
Engine RPM: 864
Car speed: 4.23 km/h
Gear requested: Second
Gear engaged: Second
Hydraulic circuit pressure: 39.00 bar
Engine RPM: 864 rpm
Car speed: 4.23 km/h
Gear requested: Second
Gear engaged: Second
Gearbox Oil Temperature: 35.20 °C
Battery voltage: 12.59 V
Error counter: 35
___________________________
Reading faults for: Automatic gearbox Marelli SELESPEED CFC300
___________________
Faults reported:
14/12/2018 08:40:49.463
Faults found.
P2905
___________________________
Reading faults for: Automatic gearbox Marelli SELESPEED CFC300
___________________
Faults reported:
14/12/2018 08:40:58.375
Faults found.
P2905
Error code: P2905
Gearbox sub-system
Incorrect engagement/selection
Failure lamp not requested
Fault intermittent
Test complete or not applicable
Minutes: 39
Engine RPM: 864
Car speed: 4.23 km/h
Gear requested: Second
Gear engaged: Second
Hydraulic circuit pressure: 39.00 bar
Engine RPM: 864 rpm
Car speed: 4.23 km/h
Gear requested: Second
Gear engaged: Second
Gearbox Oil Temperature: 35.20 °C
Battery voltage: 12.59 V
Error counter: 35

[Citroënbender]

Hello Guy, and no need to apologise for perfect English.

My first suspect in Selespeeds is the pressure accumulator. If it has lost gas pressure, it compromises shifting and can also generate false impressions of other items at fault. If you do not know how old it is, replace this item.

[bazzbazz]

This is usually caused because the Engagement Sensor is faulty and requires replacing. The fact that it actually changes gears (but does do in a random manner would suggest that it is not a Mechanical or Clutch Master Cylinder problem.

The Pressure is also fine, the selespeed system on the 159 runs at a lower pressure than the 156/147. (The electric pump is turned on when the pressure drops below 36.5 bars and off when the pressure in the circuit reaches 46 bars)

However, before doing ANYTHING, you need to check that there is the correct amount of Selespeed Fluid in the reservoir as well as the correct amount of brake fluid in the Selespeed Master Cylinder Reservoir. If you do not understand how to do either you should take it to a workshop that is familiar with Selespeed gearboxes and get them to fix the car.

You can get the sensor from shop4parts.

https://shop4parts.co.uk/?name=store&op=Details&ProdID=14058&sku=269786

On the shop4parts page given above there is a small diagram that you can click on and make larger. It will show two sensors on the Selespeed ECU the top one will be shaded. The shaded sensor is the POSITION sensor, you need to replace the un-shaded sensor below it, that is the ENGAGEMENT sensor.

Be aware, replacing the sensor can be very difficult as it has to be "pre-loaded" as you fit it.

Again - If you do not understand what that means you should take it to a workshop that is familiar with Selespeed gearboxes and get them to replace the part for you.

I normally recommend replacing BOTH sensors, as if one fails the other usually fails soon after.

[bazzbazz]

The 159 Selespeed ECU is mounted to the front facing side of the gearbox, facing the radiator.



Its the box at the bottom front in the pic.

The two Sensors in question are tucked away to the left of the ECU.

NOT the one above the ECU mounted on the metal cylinder (Clutch Master Cylinder), that is the clutch position sensor.

The big fluid reservoir on top is for the Selespeed fluid, the smaller one below it with the black top is the Clutch Fluid Reservoir.

[guy200]

Thank you guys for your kind help. I'm glad I've found this great forum... 
I don't think I'll be able to replace the sensors by my own. However I will take your advice and ask my mechanic to check both the pressure accumulator and the ECU sensor in the coming service (as for now the car works just fine. The gear shift is acting normal as I'm driving in manual mode).
Anyway I found the two sensors for sale here (buttom of the page).
https://www.alfaworkshop.co.uk/parts/159_Sensors.shtml
Part No: 71748013 (Sensor for selespeed repair module)
Part No: 6000100088 (Gearbox control unit sensor)
Are these the correct ones?


Thanks,
Guy (Israel)

[bazzbazz]

You need 6000100088, this is a Hall Effect Sensor and these are the two sensors to the left of the ECU next to the large electrical plugs on the ECU.

71748013 is a Potentiometer and goes on the Selespeed Clutch Master Cylinder that sits above the ECU in the photo above.

They are NOT interchangeable even though they look similar.

[guy200]

O.K. will do. Thank you very much.

[Pseudonym]

Sorry to hijack but bazz or CB would you have any idea where to find data for the 159 selespeed, I've been looking through the 159 elearn but either I'm blind or it's elsewhere?

Sent from my T04 using Tapatalk

[bazzbazz]

There is no information on the Selespeed in the 159 eLearn, sorry.