Auto box only first gear

[easyonthegas]

On entry to car got another "low battery warning" message, even with the car doing 200 miles the previous week. Car started as usual, but on driving away it would not change from first gear. Getting up to 3500rpm doing about 20 mph. Could not select any other gears on the paddles either, and no warning light or message.
Drove back home and phoned Mobilo who came out and plugged in their laptop reader. After testing all 9 control units, no errors could be found. Warmed up engine and it drove around block with no issues. Drove it 20 miles to MB dealer who also found no errors codes and car was driving fine.
Possible a low battery fault could be the cause, but who knows - not me or the MB dealer.
I'll post any updates, unless anyone else has seen this problem.

 

[zipdip]

Think you need to check the battery charge first you have a nearly new car so that battery should be around 12.6v at least.

 

[easyonthegas]

When the engine is running, the battery voltage is showing 14.3V on the vehicle data screen, and the stop/start works once engine is warm.

Yesterday after 500 metres of driving, the dash lit up with four messages

• ESP inoperative
• ABS inoperative
• Active brake assist functions limited
• Parking brake malfunction

Once I stopped, and switched off the ignition then back on all faults cleared. It's not dull driving this car!

 

[DrNick]

14.3V is the voltage coming out of the alternator. It shows the charging system is ok but doesn’t tell you much about the state of the battery. You need to measure battery voltage with the engine off, and probably after leaving it overnight to see if it’s holding its charge.
In reality, it’s probably not going to tell you much, but it does sound like battery issues.
Do you have a battery charger you can use to make sure it’s fully charged?
Do you leave it a long time between journeys, or do you do lots of short journeys? These things will potentially lead to the battery not being fully charged eventually.
How old is the battery? Although they can last for many years they can start to fail after 4-5 years

 

[Wearsthefoxhat]

Possibly a speed sensor playing up..

 

[Petrol Pete]

What age is the battery ?

 

[easyonthegas]

Thanks for the comments. Battery is showing 12.6V when left overnight. I have had to buy a CTEK charger to charge it up and it only takes about 6 hours to charge it.
I was getting "battery critical" warning before the car was a year old, and still get them every month. Car always starts no problem. Battery is only 26 months old now.

I agree that there are too many different faults showing to indicate just one or two sensors have gone off spec, even the common speed or throttle sensor ones.
I'll keep everyone posted as sharing these issues helps everyone find that elusive problem

 

[Flyinspanner]

Clear the faults and see what comes back.

wheel sensor, or possibly a speed sensor on the gearbox electroplate locking it into “limp” second gear.

 

[ALFAitalia]

My wife's A Class (A169 model) hangs in first when she's not driven it very far for a while. Stopping and restarting usually cures it.....or it will go into the next gear after a few hundred yards. Just makes you sound like a boy racer! Also no fault codes. If she drives it every day its fine so I think it could almost be time to change her 16 year old original battery!! Starts first time every time though.

 

[Flyinspanner]

Maybe change ATF? Has that ever been done in its 16yrs?

Battery has done very well to last that long!

 

[ALFAitalia]

Auto fluid gets changes every three years.....but as it clears with a restart I don't think its that. Yes that is an impressive battery life....maybe living inside the car away from cold and engine heat helps....I just know that as soon as the original one goes its will go to 4 or 5 year battery life like all after market batteries!! She's looking at a 2019 A Class so it might be sold before that point. My 2003 Grand Cherokee had its original battery when I sold it about 6 years ago and my ALFA (2009) had its first new battery in 2019. Must be living on the sub tropical South coast that does it....no hard winters for batteries to survive through!

 

[easyonthegas]

Getting more interesting or exciting depending on your viewpoint. Gearbox in D but stuck in first again. Called Mobilo who found C003A fault code (right wheel speed sensor). Could not clear fault so low-loader (how embarrassing) to dealer. Dealer says they have tested sensor and cleared fault so OK to drive now - which is what they said last time and the fault re-appeared three more times. Very reluctant to be the testing service for their fault finding. More to follow!

 

[easyonthegas]

After declining to take the car back, the dealer kept the car to see if the fault reappeared - which it did within 24 hours. After now changing the wheel speed sensor the car was returned. Since then, and after nearly 3000 miles (I have been across the EU) the car has performed as I hoped and expected with no faults whatsoever. Still puzzled as to why the dealer was reluctant to change the £20 sensor part, as surely the technican time costs more than that.

 

[wongl]

The speed sensor is more like 70 quid and I read somewhere that they should be changed in pairs rather than one side only.

I changed only one side when mine failed and sure enough the other side failed a few months later.

 

[easyonthegas]

Thanks Wongl. I will report in if the NS sensor starts to play up