Adaptive gearbox questions

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Sloppysod
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Adaptive gearbox questions

Post by Sloppysod »

I have read somewhere on the internet about how the Citroen 6-speed adaptive gearbox (AM6C) operates, and have lost the info/link, even after spending time going through my history so, can anyone please confirm what I think I remember?
  • 1, Initially on cold start-up the gearbox ECU will hold gears for a little longer to build engine temperature quickly
    2, Once warm it will then work to the best it can to achieve a good economy.
    3, If you are going around a corner it will not change up unless it really has to.
    4, After using the 'kickdown', it will change up again to meet rule 2.
    5, If you are going up hill again it will hold onto gears.
My second question is what sensors are involved?

Reason for questions - My car, since I bought it, will not change into 5th of 6th automatically when given a lot of right foot, but with a gentle right foot, it will change up smoothly and quickly, possibly too quickly (5th below 40 mph). However, driving to work today, it worked exactly as you would expect for about 4-5 miles, up and down no problems, but then back to not changing into 5th or 6th automatically once the engine was warm? I think it may be a temperature sensor reading wrong as today it was a bit fresh at 6:00 am, the problem is so far I cannot find any faults.
Stu 🏴󠁧󠁢󠁷󠁬󠁳󠁿

"Some cause happiness wherever they go, others whenever they go"Oscar Wilde (1854-1900)

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vborovic
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Re: Adaptive gearbox questions

Post by vborovic »

You're expecting too much out of your car ... :D ... you have DiagBox, if any involved sensor would give you a false readout (or wrong value intervals), due to a mechanical/electrical fault, believe me, it would hit you with a warning (especially engine/gearbox related) during the diag session
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Sloppysod
Donor 2024
Posts: 965
Joined: 23 May 2015, 23:35
Location: North Wales
My Cars: Citroens
1 x GS, 1 x GSX (Banger raced), 1 x GSA,
2 x CX Famililles, 1 x CX GTI,
BX, XM, Xantia, C5 Mk1,
C4 (Coupe), C4 (B7),
C5 (X7)

Renault
R4 Van
Fuego
Clio Campas
x 212

Re: Adaptive gearbox questions

Post by Sloppysod »

Gearbox problem sorted Sorted -
See http://www.frenchcarforum.co.uk/forum/v ... f&start=15 :-D
Stu 🏴󠁧󠁢󠁷󠁬󠁳󠁿

"Some cause happiness wherever they go, others whenever they go"Oscar Wilde (1854-1900)

Major interventions
C5 Steering rack @ 58,000 mi
4 discs & Pads @ 63,585 mi
2 (AM6) oil exchanges @ 58,876 & 72,378 mi
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