C5 only 1, 3, and 5 gears work, in both manual/auto

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Orchid70
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C5 only 1, 3, and 5 gears work, in both manual/auto

Post by Orchid70 »

Hi
VIN: VF7**************[VIN obfuscated, can be read by forum staff]
240000 km

Fault codes read with DiagBox:
P0925 - no info
P0949 - no info
P1800 - Fault in programming of N, Local, Permanent, MIL

I dont have much info, we bought it cheap because of this fault.

I didnt find where I could do a basic setting of the neutral - if thats what needed?

Fresch cars arent what we usually work with.
Any help would be much appreciated.
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GiveMeABreak
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by GiveMeABreak »

I guess you are feeling brave then! Sitting down?
Fault Code: P0925
Description of Fault: Gearbox fault - The gear does not engage : Not characterised. Non-engagement of the gear requested at the end of 2 s (Not N). Fault appearance when Gear change in progress (Engagement only).
Conditions for Fault to clear:
Downgrade Modes whilst Fault is active: Attempts at engaging the target gear and activation of manual mode (Gear change requests are then ignored).
In the event of a failure to engage the target gear.
  • Emergency selection of neutral (Subsequent gear change requests are taken into account).
  • Automatic mode deactivated if engagement of target gear fails.
In the event of failure after several attempts: Selection of neutral

If the vehicle has the Stop and Start system: Stop and start function deactivated
Symptoms:
  • Difficult/impossible to change a gear
  • Lack of power
  • Absence of automatic stopping of the internal combustion engine
  • Lighting of the engine autodiagnosis warning lamp
  • Starting problem
  • Timing
  • Leaks
Suspect Areas:
  • Clutch kit
  • Gear engagement sensor
  • Selection sensor
  • Electrical harness
  • Pipes
  • Hydraulic valve block
  • Electro-pump
  • Pressure accumulator
  • Electrovalves
  • Piloted manual gearbox
  • Mechanical problem (Gear selection mechanism, Gear engagement fingers)
  • Gearbox mechanics (Internal control)

Fault Code: P0949
Description of Fault: Clutch programming incomplete or not carried out fault: Not characterised. Detection that the bite point has not been programmed.
Conditions for Fault to clear: The following conditions have to be met:
- ECU woken up
- Ignition on for at least 5 secs
Downgrade Modes whilst Fault is active: If the vehicle has the Stop and Start system: Stop and start function deactivated
Symptoms:
  • Jerking/stalling
  • Absence of automatic stopping of the internal combustion engine
Suspect Areas: Programming to be carried out in after sales.

Fault Code: P1800
Description of Fault: Gearbox programming incomplete or not carried out fault: Not characterised. Selection gate initialisation not completed or not done.

Fault Conditions: The following conditions have to be met:
- ECU woken up
- Ignition on for more than 5 seconds
Conditions for Fault to clear: -
Downgrade Modes whilst Fault is active:
  • Automatic mode deactivated
  • Crawling deactivated
  • Take-off deactivated
  • Gear change prohibited
Warning Lamps:
  • "SERVICE" warning lamp
  • Sport warning lamp
  • Snow warning lamp
  • Automatic or 6-speed piloted manual gearbox warning lamps (Orange PRND triangle)
  • Display of a "-" on the fascia panel
Symptoms:
  • Impossible to make the vehicle move
  • Lack of power
  • Difficult/impossible to change a gear
Suspect Areas: Programming to be carried out in after sales
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Orchid70
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by Orchid70 »

Nooopeee... I have been dragging this - we have had the car since spring.
Hubby was a bit fast.
I have felt its going to be scrapped....

Ok - so I have two fault codes for programming. Would you try with that, first? Or do you recond, I have those two last fault codes because of the P0925?
In case I should try programming option - is that possible to do with a China DiagBox?

Cosh - must be translation from Frensch! I can hardly understand what they mean =)
Could it perhaps be the clutch??

Thank you again GiveMeABrake!
wheeler
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by wheeler »

Definitely worth trying a gear & clutch position re programming. When doing it though its very important to have good battery support as it can sap quite a bit of power doing it. Have another running car connected via jump leads, If the voltage of the battery drops too low the procedure can fail.
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Orchid70
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by Orchid70 »

Thank you Wheeler!
Do you know where I can find this programming option in DiagBox?
I do also have Autel and SnapOn, they are a bit easier to navigate in.
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GiveMeABreak
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by GiveMeABreak »

That would be my suggestion too - nothing to lose. It could be either the P0925 fault is coming up because of the lack of programming - or it cannot be programmed because of the P0925 fault.

If you run the Global Test in Diagbox first, then select the piloted gearbox ECU and confirm, you should get into the options for everything you can do for that ECU.
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Orchid70
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by Orchid70 »

Thank you Marc!!
I will test!
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Orchid70
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by Orchid70 »

I seem to not be able to do any programming with Diagbox.
The gearbox ECU (computer?) is not recognized - no name. See the pictures.
Nowhere could I do any programming or basic settings - "This computer does not allow it" was the response.
So I took out Autel.
I was able to do one thing succesfully but after that the fault codes P0949 and P1800 came up.
It was called "Complete programming" - and it did try to program the Neutral position - I got "Completed" in the end. Where as, all the other options stated "Not succesfull".
On top of this - two new faults were precent (we lended the car out for couple of days):
P12A5 Cyl2 low quantity of fuel or low compression, Intermittent - I guess when it says "Interval wiping" it is suppes to mean intremittent...
P1445 Particulate filter needs changing

gearbox ecu unknown and in safe mode:
gearbox ecu unknown and in safe mode.jpg
This one is the the Central voltage stabilizer and says: computer precent but remote programmed missing
computer precent but remote programmed missing.jpg
What are all these options in Gearbox in Diagbox - none of them worked and Autle only had 3:
What are all these options.jpg
And last question:
Where is the best place to find what gearbox a vehicle has? Is the one in ours called AM6? Other places call it 6MT.....

Thanks :)
wheeler
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by wheeler »

Well its not the AM6 or the AL4 as these are both proper auto boxes. The CFC300P I think is the only one there that is a piloted manual box.
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GiveMeABreak
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by GiveMeABreak »

If you look back to my previous post, you won't be able to programme the gearbox ECU if there is a communications fault - the same problem that is likely preventing communication may be what is preventing Diagbox with 'talking' to it. So I would go and double check the actual connection on the gearbox ECU - specifically the pins in the connections as these have been known to come loose inside the socket.
wheeler
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by wheeler »

Im not saying that there is not another issue here but just because Diagbox doesn't identify the exact ECU doesn't mean that there is a problem.
Its not unusual to see this on Diagbox, even when scanning a vehicle with no known faults. I find ABS/ESP systems seem to be the worst offenders with this.
If there was a communication problem issue I would expect Diagbox to say no communication rather than ECU not identified.
If you are able to read fault codes from the gearbox ECU? then i would say you have communication with it?
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Orchid70
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by Orchid70 »

Im trying to understand the gearbox.
I cannot connect to it with any of the diagnostics - when I choose CFC300P.
At all.

I can "connect" to the gearbox if I choose: AM6 and it gives me the above fault codes and I can read the ECU info (PSA reference 9666883580, Program reference 773988, Version 0305).
The fault codes P1800 and P0949 can be "erazed".
I can read the gearbox oil quality (0-20) to 17.

If I "connect" to AL4, I can read the ECU info and the fault codes are this time: P1800 and P1212 CANNOT be erazed...

The electric part of the gearbox has the number: 9674693580
The connectors look fine on it.

I was searching fo blown fuses and found out that BSM has been changed before with a used unit. It was filled with leftovers from mice. But the unit is sealed with epoxy - so that was a wild goose chase.
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Orchid70
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by Orchid70 »

So we have decided to scrap the car.
And the tank is more than half full
I thought I could "bleed" it out through the return pipe to the tank, with ignition on.... But none of the pipes (three) gives me anything, turning the ignition on. I can only pump out with the hand pump on the filter.... and thats going to take me hours.
I couldnt fins a otpion in the OBD program either. Most brands I can operate the in tank pump with computer. Is there a in tank pump even?
Any advice how to get the diesel out the easiest way?
Thank you!!
Gibbo2286
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by Gibbo2286 »

If you put your can on the floor and add a long hose to the hand pump outlet so that it's below the tank level give it a few squeezes and it should syphon out.
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Orchid70
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Re: C5 only 1, 3, and 5 gears work, in both manual/auto

Post by Orchid70 »

No it doesnt work.
Stupid car.
Thanks for the idea though.