Discovery TD5 auto box problem

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Hi the LR description of that code is

"P0721(21)* Downshift safety monitor prevented downshift which would have caused engine overspeed" corroborated with the stall test result above 2800rpm seems very like a clutch slip.... IMO that's what it is, not electrical at all
it’s very strange as it only ever does it when I’m hard on the throttle it’s Asif it can’t decide what gear to be in sort of like it changes 3 times then brings m+s on. I’ve just done another stall test it revs to 3000rpm.
 
it’s very strange as it only ever does it when I’m hard on the throttle it’s Asif it can’t decide what gear to be in sort of like it changes 3 times then brings m+s on. I’ve just done another stall test it revs to 3000rpm.
If it's a clutch slip is not strange at all IMO, the symptom is very similar with a slipping clutch on a manual + that the fault code and stall test are confirming it... i know i's a bad news but i'm 99% convinced it's that even though it's simpler to fix than if it was some strange electrical issue ... albeit it can be a bit expensive
 
Hi the LR description of that code is

"P0721(21)* Downshift safety monitor prevented downshift which would have caused engine overspeed" corroborated with the stall test result above 2800rpm seems very like a clutch slip.... IMO that's what it is, not electrical at all
it’s very strange as it only ever does it when I’m hard on the throttle it’s Asif it can’t decide what gear to be in sort of like it changes 3 times then brings m+s on. I’ve just done another stall test it revs to 3000rpm.
If it's a clutch slip is not strange at all IMO, the symptom is very similar with a slipping clutch on a manual + that the fault code and stall test are confirming it... i know i's a bad news but i'm 99% convinced it's that even though it's simpler to fix than if it was some strange electrical issue ... albeit it can be a bit expensive
just checked nanocom p1884 and p0721 again would p1884 relate to slipping clutch too? Thanks everyone for the help also if it’s the clutches slipping I’m guessing it’s torque converter that needs replacing not box?
 

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it’s very strange as it only ever does it when I’m hard on the throttle it’s Asif it can’t decide what gear to be in sort of like it changes 3 times then brings m+s on. I’ve just done another stall test it revs to 3000rpm.

just checked nanocom p1884 and p0721 again would p1884 relate to slipping clutch too? Thanks everyone for the help also if it’s the clutches slipping I’m guessing it’s torque converter that needs replacing not box?
"The planetary gear train is a mechanical system in which the gears are connected with a set of bands and clutches. "
So no, not the torque converter.
"The torque converter connects the engine to the transmission and uses pressurized fluid to transfer power to the gears. "
So it doesn't have a clutch.
 
if it’s the clutches slipping I’m guessing it’s torque converter that needs replacing not box?
The P1884 can be the result of slipping clutch so the torque is lower than expected at a certain rpm, the clutches are in the autobox not in the TC if it was about the TC the fault code and stall test result should have been different, IMO you'll have to bite the bullet and refurb or replace the box
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