I got a problem with my gearbox merc 817 the box keeps on selcting 8th gear when i change from 2nd and want to go up 2 gears to 4th…to change like that i have to keep the stick held forward and it should go up 2 gears but sometimes goes to 8th…anyone know why?or a cure.and noone say sell it or take it to merc as already been to a merc dealer at ipswich and they havent a clue(dont think they knew much about the gearbox and palmed me off about it will do that every now and then)
The first thing we always looked at with EPS when it started mis-selecting gears was the Road Speed Sensor.
have you had a read of the hand book
not sure which eps you have got .?
but they used to have a section in
the book which showed you how
to retrain–re programme the box,
have you tried sending a e-mail to
mercedes england and ask them
for advice, it has got to be worth a try
as you will be kicking yourself
if the answer turns out to be
a simple easy fixable fault,
Hi jayeastanglia, I’d go with brit pete’s advice on this one mate.
Chances are that it’s a sensor, but are you getting a fault code 
IMHO, the advice you say you’ve had from the dealer isn’t good enough… 
jay
i’d go with the above
i’d forgotten about the reset option
hold the stick to the left with the button held in or something like
im sure someone will be along to tell you for sure how to do it
vernonbish777:
jayi’d go with the above
i’d forgotten about the reset option
hold the stick to the left with the button held in or something like
im sure someone will be along to tell you for sure how to do it
Same here mate, let’s call it a failing memory. 
There’s also a way to get the system to do a self-diagnostic that reveals all fault codes, but I can’t remember how to do that either.
Once that’s done though, I have a feeling that it won’t be a big job to fix. 
Good luck with it jay, sorry I couldn’t have been more helpful 
Try holding the button in, pushed Left turn the key off but hold it in for 30seconds then turn the key (I think it might reste the memory cant be to sure its been 4years since last in one
K.Adams:
Try holding the button in, pushed Left turn the key off but hold it in for 30seconds then turn the key (I think it might reste the memory cant be to sure its been 4years since last in one
yeah do all that plus hold clutch down and it goes hiss click click hiss click click the lever goes a little more to the left and its ok for a while the it does it again into 8th…i got no fault codes but will check out the road speed sensor at the weekend…i wont name the dealer as they have been helpful before but they did admit they didnt know much about the gearbox as its a bit rare in a 7.5tonne
dieseldave
“failing memory”
do you mean ours or the EPS’s ■■? 
Having owned an Actros for 7 years and been at war with MB all that time because of various faults I pass on this finding which many will prob find unbelieveable.
The electronic components which control most of the features on the Actros can have their function knocked out by radio signals,while passing power lines can have the same effect.
Any prob with a Merc have a look round for a radio mast or power line and consider whether that may be interfering with the electronics.
As for why I kept the rig for 7 years,it amused me,but shortly i will give you all the opportunity to make your own opinion since I was obliged to film this effect,
the effect is known as EMI,electro magnetic interference.
As for the dealerships,a senior member of MB’s staff did advise that over 60% of their dealerships are sub standard,which wasn’t exactly surprising,but it is amusing that these clowns actually want to undertake training for the driver CPC.I intend to stop them…
armagedon,
Trying not to drift too far off topic here…
I’ve heard of EMI before, in the cold, dark days when I worked in an office the company I worked for had the great idea of having a mobile phone mast put in their carpark to bring in a bit of extra cash. It was installed and forgotten about.
One day they turned the mast on, at closing time, everyone who had a Volvo parked in the car park returned to their car to find it wouldn’t unlock using the remote!
The masts owners were called in, did a survey and said all was ok, and it was just a coincidence… then Volvo UK came along along with an independent surveyor and produced a report saying some sort of shield had to be put on the mast at a certain height to stop the problems.
Man came along with a bit of aluminium, put it around the bottom and hey presto problems solved!
Hope its not too far off topic, sorry Jay!
Alex
EPS > craporama
EMI - used to get a problem with the cruise-control on my old 500DAF. Every time I went under HT cables it would disengage. Doesn’t happen with my 530DAF though.
vernonbish777:
dieseldave“failing memory”
do you mean ours or the EPS’s ■■?
Hi vernonbish777, it probably applies all around mate.
I’m a bit clapped out, and I’m sure it’s possible that lots of other things are too.
As soon as K.Adams posted the method, I recognised it. 
Thanks K.
EPS is a very inteligent system. It knows what gear you need for any given situation and will automatically select a different one. It also detects the speed at which you need to get on the bay, and delays selecting reverse in linear proportion to urgency. It is capable of displaying fault code GS26 at any time, but will do this only when you are blocking at least 20 other vehicles or at roundabouts during rush hour.
Once you master its little foibles the inbuilt multiple personality will kick in just to keep you on your toes. Drivers who have seen military action should be aware that the sudden burst of machine gun fire is normal, and the urge to duck below the dashboard should be avoided at all costs.
Other than that is is a wonderful gearbox
i may have fixed it with the help from a truck driver from felixstowe port who had a simalar problem with his a few years ago…we took the speed sensor off and cleaned the connections and also reset (I think it was the clutch lever switch)and reset the box and so far!!i only been to ipswich and back it hasnt gone into 8th from a standstill…I will know more on saturday as off to collect stuff round essex…just got a few more things to fix on sunday as got a slight air leak from somewhere as if left standing for 2 hours it will dump the air from tank 2.cant hear any hiss…