E39 523i Steptronic transmission light

Hi and welcome to the forum.

Firstly has your car got silly sized wheels on it? 

Secondly is there a difference in tyre size and hence rolling radii between front and rear axles?

Messing about (changing from standard) with tyre sizes/rolling radii can upset both ASC/ABS and the autobox as they use the speed of each wheel in relation to the others as input into their processors before deciding what action to take.  If you alter the wheel speeds in relation to each other or significantly from default values, can play havoc with the ASC/ABS and the autobox.

The ABS/ASC and transmission faults might be linked.

Your ABS/ASC system uses a speed sensor located at each wheel to monitor the speeds of each wheel to control the ABS/ASC system.  On an auto E39 the front wheel sensors send signals to the transmission ECU telling it when to change gear. 

A symptom of a knackered front wheel sensor on an auto E39 is rough transmission shifts.  This will first manifest itself as ASC/ABS warnign lights on on the dash.

But then again you could have an ABS/ASC fault similar to Nigels post and an unrelated transmission fault.

It needs a proper diagnostic check.  My local garage struggle with my E60 on diagnostic but BMW can read it 100%.  It depends on how good their system is.

Regarding the transmission...

The best thing to do is take it to an Automatic Transmission Specialist who can diagnose the fault.  A good specialist will be able to diagnose your cars brain and find out whats wrong.

BMW can also tell you what is wrong with their diagnostic equipment but they will not be able to do anything on an autobox other than top up the fluid or swap a complete tranny in and out.  You could then go armed with the BMW diagnostic info to the tranny specialist.  I did this when my E39 went into limp mode.  Not knowing any better, I took it to BMW who told me what was wrong, charged me an hours labour for the diagnostic check then told me that they could not fix it but to take it to a transmission specialist, whom then sorted it for £700.  I got new pressure solenoids and shift solenoids (shift solenoid #4 was faulty on mine) the valve body overhauled and a transmission service.

It could be anything on anyone of the gazillion components in your autobox that is faulty.  There is a temp sensor in the autobox, which again will send signals to the contorlling electronic brain.  It is not unheard off for the insulation on wires which sit in the sump pan to degrade and casue a short.  Easy fix once found. 

If the tranny is overheating check that your transmission fluid cooler matrix is clear from muck and debris.  This is located either next to the main engine radiator or between the rad and the aircon matrix.  Once the main engine rad is out the way the matrix is easy to see.  Once I had removed my engine radiator I could clean out the dust and leaves that had collected over ther years.

Once the transmission is fixed you can then turn your attention to the ABS/ASC system.

At that age of car, I would make sure that you get your transmission serviced even if it is an ABS/ASC fault that has upset your tranny.

HTH

Andrew

The code of 045 is meaningless I'm afraid.  I can't link it to any of the codes I've got. If you have a P0710 to PF0714 inclusive codes that corresponds to a transmission temp fault.

I feel your pain but I reckon it would be worthwhile spending no more that £50 or so confirming the fault codes.  You would need to take it to somewhere else than before esp if you admit that they weren't very helpful.

If a trader looks at your car and clocks that all the warning lights are on the dash your trade value will plument.

No speedo usually means that one of your rear wheel sensors (sorry can't remember which one) is not working, which could be the source of your problem.

Noughtbboy,

 

Did you ever get this problem resolved?

kabukidrive wrote: Noughtbboy,   Did you ever get this problem resolved?

Hi everyone,

Sorry for lying low. I took it into a specialist with the
"proper equipment". They say it is not the ABS controller
or the wheel sensor at all. It is solely down to the
automatic transmission oil temperature sensor which is
sending conflicting info to the ABS controller resulting
in all the similar problems.

They are going to replace the faulty sensor (+/- £100)
and 3 hours labour to "drop the box" in-situ (£150) and
put in about 5l or auto fluid as the torque converter
does not need to be removed.

I will ask them to replace all the ATF as it may as well
be done properly whilst we are all open. I will be
getting 9l of Carlube Dexron III ATF for them for around
£40 hopefully.

So the total cost will be around £250 +VAT and then £30
for the diagnosis and £40 for the ATF. So hopefully about
£360 which is more or less what the ABS controller
programmed and fitted would cost.

I can almost see that the ABS would have to be done as
well because I am feeling really "glass half filled" at
present but will cross the bridge if it comes to that.

So lets all hold thumbs.

NB

OK, going to to the report back and the news is not good.

Firstly I made an error...it was not the transmission oil
temperature sensor it was the speed sensor in the 'box.

As they explained, it takes readings from the wheel
sensors as to the speed which allows it to change gears
correctly. This faulty sensor was getting/giving false
readings which was clashing with the wheel sensors and
the ABS controller which is what was causing the fault.

The bad part was upon opening the box, they found water
mixed in with the oil. The mechanic said he had never
seen this before unless the car had been in flood damaged
or hauled out of a river.

As they went through the debris in the oil pan, they
found metal shavings. So basically they said the gearbox
needs to be replaced.

All they could do was replace the sensor (actually they
replaced an entire unit which included the sensor for no
extra charge) and filled up with ATF and said they are
not guaranteeing it would work. And guess what? It
didn't!

They reckon as the box heated up through being driven
(usually 6 miles or about 15 minutes) the water would
heat up, steam and leave the (contaminated) oil level low
and unable to lubricate causing the damage.

So, now have a good looking car with 74k miles on the
clock which will have to either be scrapped or sold as a
non-runner. Absolute pity as the only thing the
car cost in almost 4 years and 20k miles of ownership was
a service of £340 or so where I went to town replacing
oil, fuel, pollen, air filters etc and front pads and a
brake light bulb during which time it never missed a
beat.

http://www.youtube.com/watch?v=Wn_iz8z2AGw

NB

[QUOTE=Andrew Rolland]

I have heard of the odd ZF
autbox getting water in it.  The auto Mecrs were crippled
from this as thier transmission fluid cooler was integral
with the cooling system radiator.  Transmission fluid
cooler sprung a leak into the radiator and coolant got
into the transmission fluid and then into the tranmission
causing havoc.  My E39 had a separate transmission fluid
cooler so there would be no chance of this happening.  I
can't think how the water would have got in?  Did they
offer any explanation?

Water in the box would then short out/cause erronious
electrical signals...and then damage mechanicals.

Correct

Did whoever looked at your transmission actually test
the fluid for water contamination?  There is a specific
test that a transmission specialist can do.

Not specifically that I am aware of but they
brought it through to show me and there were two distinct
layers - the oil and "not the oil" that they claim was
water and who am I to dispute that it is water.

What size were the metal shavings?  Was it like chunks
of gear teeth or very fine swarf? 

There were fine particles and then there were
also a few that looked like grated cheese - i.e.
shavings. And these were all collected in the oil pan
that he showed me so I assume it came out with the oil
and not magnets.

There are magnets in the transmission sump to collect
metal fragments to keep them out of the meshing gear
teeth and fluid channels.  It is quite common to see very
small particles/swarf stuck to the transmission magnets. 

I removed very fine swarf from the transmission
magents when I got a new filter on my E60 and when I
dropped the tranny sump on my old Senator.  Neither car
had a huge amount but it was like very fine oily sand.

A recon autobox could be had from probably less than
£1k. Still a big hit but as you said earlier it is what
the car is worth.  Bummer!

As you say, bummer. Well, will put it on the
'Bay soon enough. Sorry for the late reply to this but
the notification was sitting in my Spam so shows you what
Google think of you!

Thanks to everyone for all help.

Regards

NB