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tellboy

Mmt Gearbox Yet Again Flashing N In Drive Positions

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Toyota YARIS MMT Gearbox 55 Reg

Previous relevant history. Gearbox selection mechanism changed on warranty. Present Mileage only 16,000

1 Gear lever is in Neutral and showing N on display. Depress footbrake until engine is running smoothly . Release handbrake press footbrake and select E (or R)

2 The display instead of showing 1 or R just flashes N in the drive positions.

3 Reselection tried a number of times from 1 to N to R but still flashes N in the drive positions or a non flashing N in Neutral as normal. It will not engage gear and move.

4 If I turn the engine off I am then an unable to restart until the next day (as advised by Toyota Service Department) to let the brake pressure reduce overnight to enable the starter to engage.

5 Next day it may start and run normally through all the MMT gearbox gears and reverse and even the manual option. It will then randomly repeat the problem having worked during the day.

6 It has happened 5 times but is too unreliable to trust away from the house.

Note I have tried both options in the handbook of depressing the switch on the gear lever with a screwdriver with ignition OFF and Ignition ON as sometimes it is stuck in gear but this does not release it.

I can get it back to Neutral sometimes by jacking up the front right hand wheel and rotating it until solid and getting someone else to do the procedure in the handbook.

If I try to push the car sometimes it is able to move and correctly in Neutral but still displays the flashing N when I select a gear.

The Car is always correctly put in Neutral before switching the Ignition off and registering on the display as N.

I hope this helps you to diagnose the fault which has happened about 5 times in 2 months.

The car is obviously unusable in this condition and even happened when I was about to transport a hive full of bees.

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I regret it is unlikely anyone will know anything about the bag of junk called a MMT except technicians.

(Bees like travelling in my Yaris d4d... no problems at all)

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Bit cruel that from Madasafish.

Sad that at only 16000 miles you have such problems.

Looks like a trip to mister T. Hope its something easy to fix so that you can continue to enjoy your car.

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"Bit cruel that from Madasafish."

No, quite accurate, in my opinion and experience. :)

I wonder why Toyota are gradually ditching it into the scrap bin of failed experiments?

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"Bit cruel that from Madasafish."

No, quite accurate, in my opinion and experience. :)

I wonder why Toyota are gradually ditching it into the scrap bin of failed experiments? Possibly because of many customer complaints as to it's uselessness? Mine included.

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Thank you Madasafish.

I actually agree with your unhelpful reply on MMT and go further to say that the rest of the car that is attached to the gearbox is fairly awful even your precious d4d.

I now regard the Yaris as a mobile skip having fallen for the Toyota Hype of reliability and customer service. Luckily I have a proper car that I dare to drive away from a bus route as it is made in Germany

I now know the problem as Toyota got a diagnosis code somehow and the repair involves a component with electrical solenoids or relays attached to the manual box which they can repair but will be in the very high hundreds of pounds plus Labour.

As this is more than the car is probably worth 55reg even with low mileage I wonder if anyone on the Forum would think it is worth doing.

When I was waiting in the Service department............a salesman appeared........

Not very good timing was it ?

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I've no experience of these automatics but given your general feeling towards the car I'd say part ex it into the trade as opposed to spending £1000+ on a fix which isn't guaranteed to work.

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An update now that it this is diagnosed in case it helps others with the same problem.

A survey by Toyota on the rest of this low mileage Yaris suggested it was probably worth going ahead.

The Fault was the electrical switching mechanism within the MMT Shift and Select Actuator Assy Part Number T33960-52040 Qty 1.

The component cost from Toyota was £794 plus 20% VAT.

Total with Removal and Replacement was £1097.

To summarise for Search Engines.

Intermittent Fault about 5% of gear selections, MMT Yaris, Flashing N when selecting E or R and no drive will be in excess of £1000.

Edited by tellboy

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A picture of the component replaced

post-49968-0-87870200-1345026338_thumb.j

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I also had the flashing 'N' problem, lumpy tickover and stalling at roundabouts. I bought a MaxiScan MS300 but it showed no errors. The only help I found was http://svaret.free.f.../CP5013_0_1.pdf which refers to Corollas made in UK and Turkey. My solution was using a 12mm socket and medium extension loosen the three bolts in slotted holes on the top pate of the clutch actuator. Push hard on this plate to rotate it anti-clockwise and while applying pressure re-tighten the bolts. That's it. My 9 year old Yaris now goes better than it has ever done. It is a lovely car with better gear changes than I could ever achieve with a manual. I first had a problem with the transmission about two years ago-most instrument lights flashing loss of drive and a 15 minute wait before it would restart. I was quoted £2080 for ECU and actuator. I asked the dealer to replace actuator only (£625.10). This got it working though changes were poor. Luckily I asked them to leave the old actuator in the car. I found it was lubricated with a strange grease which had dried out and was stiff. Assuming the same grease was still used I extended the spout on a can of Plusgas by 18 inches and squirted fluid into the new actuator via the rubber gator. This made a noticeable improvement and was probably all that was wrong with the old actuator.

I would appreciate help finding a copy of the MMT service manual (RM100E?) so that I can set the preload properly.

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I know this was a year ago, but did this repair fix the problem?? Having a similar problem myself.

Thanks

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RG26,

Can you give me any details/tips on how to do the lubrication.

David

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Having been told that toyota software is required to reset the controller if it is disconnected, I softened the grease in situ. I extended the nozzle of a PLUSGAS aerosol can by about 18" using plastic tubing. I inserted this tube into the actuator via the rubber gator round the push rod connecting the actuator to the clutch. The push rod is about 7mm diameter and is parallel to and behind the electric motor, you have to lean right over the engine to see it. Opening a gap round the rod with a small screwdriver helps getting the tube into the actuator. I hope this helps, it took less time to do it than it has taken me to work out how to explain it. I definitely quickened gear changes.

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I have had this problem in fast flowing traffic. It is dangerous. Report it to VOSA so hopefully we can get a recall for all the customers that have been left high and dry with this inherent mmt problem.

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My wife's ex-Fiat 500 had the same problem with its dualogic semi-auto. It kept flashing in N and would not move. It the started cutting out, once on the outside lane of the M6!! Fiat could not fix it. Eventually got out of the cars contract and got a different car with a traditional automatic.

I think these semi-autos are too much hassle but they give good mpg and emission figures so manufacturers use them. I'd rather take the hit with mpg and tax and have a proper auto or the very smooth cvt boxes. Toyota at least seem to be phasing out the mmt for the multidrive cvt gearbox.

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Given that they screwed up the MMT, the chances of their VVT working is roughly nil. Why can't they just use standard auto boxes from Germany like everyone else? I have had two MMT boxes and both packed up at 50k kms. Rubbish. You just need to read the workshop manual to realise what a bag of worms this is. You need to CHANGE (not upgrade the software..) an ECU when you adjust the clutch ferchrissakes.

Avoid the VVT like the plague and I would also avoid their hybrids. Until you have worked with the Japanese mentality you have no idea...

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and BTW, they do not give better mpg or emissions in practice than proper boxes - manual or auto. The reason they use them is that they think they can cut down costs by having high volumes of the same base box.

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Hi People,

I've just signed up to contribute to this thread and i hope it helps someone. My dad's car (2006 aygo mmt) was having the intermittent fault where the transmission red light would go on just after starting the car. The 'N' neutral light/letter would be visible and solid on but when I moved into another gear, it would flash. He couldn't move the car.

After a lot of investigating I learnt the following. The gearbox is actually a manual gearbox but with an electronic clutch actuator and a shift/select gear actuator - these both do what we do to manuals, they replace needing to push a clutch pedal or physically move manual stick.

The N light typically flashes when the gear the MMT ECU thinks one thing but actual transmission thinks another OR there is a sensor fault so its sensing something unusual.

Now toyota were quoting just over £1k to diagnose and replace parts to fix my dad's car so i had a bash myself.

You will read on forums that one one sprayed a lubricant into a rubber bellow of the clutch actuator which sits on top of the gearbox housing. First I looked at my clutch actuator and I noticed that the clutch actuator was pushing the clutch fork lever- as if it was taking the manual gearbox out of gear - akin to pressing the clutch. When the engine is off, the clutch actuator is supposed to go back in and release the pressure from the clutch fork lever. Have a look, if the lever is push far left, it means either the CLUTCH STROKE SENSOR is faulty or the clutch actuator is jammed - and this is where some people have succeeded in spraying lubricant inside it.

For my dad's car, the problem was the CLUTCH STROKE SENSOR - it sits on top of the clutch actuator. It is removed by 2 philips head screws. You can easily remove it and replace it BUT you must note that the little spindle inside it turns nearly full circle so it knows when the clutch is electronically fully depressed or not. Just a note for people replacing the sensor: you push the sensor back on the housing of the clutch actuator making sure the connector plug part is at 6'clock position (where you found it before unscrewing) AND while the screws are hot it, it must be able to rotate about its position to the 10'oclock position. It must stop itself turning after the 10'oclock position and stop itself going to a 5o'clock position. If you don't ensure this before !Removed! it in, the clutch actuator will break the sensor's spindle. Our sensor somehow had taken water in because i saw corrosion on the pins and water got inside it. I replace the CLUTCH STROKE SENSOR and bingo all was back to normal again!

You will read online about ways to reset the MMT gearbox. ONLY do this if you are replacing a part (esp any of the two actuators) otherwise the simple fix of replacing the sensor above will mean you will have to lock the clutch position, initialise the clutch actuator and then initialise the MMT ECU and then teach the car when to change gears.

You may read some people have successfully "loosened 3 bolts on the clutch actuator" then rotated it anticlockwise then retightened. I realised that they were just reducing the slack they may have had in their clutch actuator and the clutch fork lever. I can't really see how this helps apart from if your car is acting like your clutch is slipping. If one was to lock the clutch via the service instructions (google blue-print initialise MMT ECU - its a blue pdf) then reinitialise the clutch actuator, you will find it will pull the pin in to lock it (for removal) and on initialising it, it will extend out to take out the slack before disengaging the clutch. It is also this mechanism which gives the car its "creep" on hills. The ECU will remember the position of the clutch fork lever so its far better than simply loosening 3 bolts and rotating the whole clutch actuator and tighten.

Lastly, lets say the your clutch was going in and out as normal, next is to check if the gear selector actuator (the one in pics where you can see 2 big motors coming from it). On top of the gearbox housing, just infront of the clutch actuator, there is a vertical tube/extension in front and above a sensor. You will see on top of it is a hex recess for a very large allen key to open it, unscrew this cap. its perfectly safe to do. inside it, you will see a flat head screw looking metal thing inside. This is actually the top end of the gear selector rod. You can actually manually change group of gears by simply using a screw driver and turning it SLIGHTLY either clock or anti-clockwise. To test this, first see what position the slit is on top of the rod (whats visible after removing the allen key cap). If its at 12-6pm position, it means its in neutral and if the car is off and was last in neutral, means the gear is correct and this means a sensor/clutch actuator is the problem. If you find that its either in the 2-8pm position or the 10-4pm position, then you know its in the wrong gear. Put the gear stick selector in the car into neutral and then use a screwdriver and put the rod in a 12-6pm position. You will actually hear you manually changing gears. Then try start the car and you may be lucky that the selector mechanism was jammed and after unjamming and you correcting the gear, it works.

Lastly, Both the clutch actuator and the gear selector actuator are just gears and cogs and I can't see what can go wrong with these and so this leads me to believe that our probs are sensor problems which are part of these actuators. Perhaps Toyota replaces the whole actuator and this is why its expensive. Toyota sell the sensors for £150 incl VAT. It sorted my problem out.

Hope this helps someone.

(As Google didn't have may threads coming up describing this problem, i'm putting these words below so that anyone searching google will find this post. flashing neutral N dashboard red transmission warning light can't select a gear no gears slipping clutch.)

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Thanks for that. Useful information.

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A picture of the component replaced

Sorry for bumping this old thread but relevant to my issue.

I cant imagine what could be wrong with that actuactor? Any signs of wear or damage? Those are mechanical parts. Unless the solenoids at the top are causing the problem, but these should be replaced alone and not entire mechanism.

As RG26 states, I bet spraying some lube in there it would solve problem.

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hello

i have to add something here...since i had same problems i ve spended hours and hours reading posts worlwide...

why? we dont want to spend money in the air...ok.

toyota mechanics knows for sure how to fix mmt's but they charge from 500 to 2000e.

both rg26 and bazhok are rigth

1.gear actuator:if for any reason its been removed or cleaned or u think that its lost its settings just take it out of the gearbox,connect to 12v(car Battery) in its motor socket so the rob of the actuator will come out to full lenght.if it pulls in, connect oposite.the acuator has a sensor on top which reads only when the rod is fully out or fully in.<<<ecu and gearbox never reads the lenght of the rod until full length ro sorten,so when ti is in other place gears just stop changing and N flashes>>>.

This M A S T be done for sure!!! if u put the actuator again on the gearbox with rob oppend(FULL LENGTH) take care that the gap attached with the "clucht rob" is no bigger than 1mm.toyota says no gap for mmt's but 0.5 to 1.5mm for manuals...isnt the same box??

If other parts are working rigth (clutch,sensors,etc)then ur car will work well.

what rg26 has done was right.loosening the 3 bolds, he moved the actuator in a better possition(lucky man).it dosent move clockwise,just left or right by the oval screws.lubed the mechanism is good because it hasnt much grease in it.

2.clutch:if clutch and its plate are worn this is another reason of the problem.

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Hi,

I have an old (2004) verso corolla with an MMT gearbox. I'm currently experiencing the flashing N problem, where the gears freeze at junctions and roundabouts. I know its very expensive to repair at Toyota, but some of you seem to have found a cure for this issue. Unfortunately, I have very little technical expertise, and would be reluctant to try any of the fixes myself. Can anyone recommend a garage/ mechanic in the Midlands who might be able to carry out the repair at a much more reasonable cost?

Would really appreciate any suggestions.

Many thanks.

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sory kaa,i am from greece...

1.look for clutch disk wear(most common reason because of heat)

2.check the actuator(lubricate inside if u can)

3.check sensors

these are common reasons for these problems...

many say that a reprogramm at a toyota service wikk fix the problem

my toyota service always starts saying "its the clutch disk" 500e cost

it s difficult to have a sensor burned out but clutch actuators go down every 50 miles

hope this helps

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Kosta i am from greece can u send me pm i have problem with corolla e12 mmt

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Hi,

Have a problem with the MMT Gearbox on my 06 Corolla since I bought it (2010), but it started happening very often recently and it's EXTREMELY annoying... When I bought the car it had 77k miles and it happened within 10 months of purchasing...then i change actuator and clutch in toyota and after 1 year started again

It's a 05 Toyota Corolla 1.4 D4D with MMT gearbox (semi-auto) - manufacured in UK.

;

Problem is that every now and again (in the last couple of weeks it happens nearly everyday), when I slow down and the gear box goes into 1st gear (for example, at trafic lights) it goes into Neutral and the fault lamp for gearbox lights on the dashboard. It happen when in both Semi-auto mode and Manual mode...

There's no way you can get it back in gear unless you switch off the engine, wait for 30 to 60 seconds and switch on again.the clutch slippin in changes to all gears

I've read several forum threads on this issue (some old ones), but couldn't find an exact answer for what is causing the gearbox to fail and what would be the proper fix.

Have anyone else came across this issue and happen to know more?

Cheers!

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