yet another trans failsafe error
 

last sunday I went out in the car to take a friend home , got in the car and she started ok however the battery seemed a little low on power, but she started , she then threw a trans failsafe error , so i turned her off and left her 5 mins then started again , started ok , but still popped the trans failsafe error , I thought it was a bug so carried on , she drove perfect , no other problems no gearbox issues nothing , any who, I got told to get the battery checked took it to battery shop they said the battery was ok but my alternator was a little "lazy"

as in I fired car up no throttle and the output on the alternator was low, gave it a tickle on the gas and the voltage popped up
any whoo , this morning , after no other issues I got home , I decided to read the codes using my laptop , couldn't see any so I reset my codes, , ive now got...........
no speedo , no rev counter, dcs, abs and TC all on , temp and fuel guage on full , and she is definatly stuck in 3rd
so I decided to buy another battery just to be on the safe side, disconnected battery for 1 hour , put new one in and started it up , still same issues

any ideas??

Steve

02 4.4

Alternator not charging correctly is a good start. The electrical systems on these BMWs are finicky and require the proper voltage.

was looking at alternators tbh , the guy that said the alternator was lazy explained it like this

he told me to fire the car up after the initial battery test, said battery was ok, then told me to fire car up , with out my foot on the gas , he said the output on the alternator was a little low (idle) but when i accelerated up to 2k , he said the voltage was ok, then when i let it idle again he said voltage was ok , ??.
which is weird

but i got an update ,

i put new battery on today (bosch s4) even with the new battery on i still got all the errors, so i thought , yeah its dead.
went out tonight before work , just to see if it was still the same , and low and behold , everythings OK?.
no warning light , everything OK

still going to get it checked thought cos somethings not right

Could be failing voltage regulator in the alt.

shes going to get tested on Thursday , so ill let you know :)

errors are as follows
DME
220 DC transmission EGS?AGS Can time out
221 DD ASC?DSC CAN TIME OUT

EGS 130 82 Can time out ASC
128 80 monitoring can bus (p0700 . p1747)

As Cool Hand Luke would say "What we have here is a failure to communicate. Looks like there's no communication between your scanner and the EGS and the ASC module/computer.

:iagree:

Or the brushes in the alternator are worn to the point that they sometimes don't make contact. A new voltage regulator comes with new brushes.

I have however thought of something..................
when I fitted the new battery, the errors and the problems were still there
I then left the car 9 hours, fired it up , everything was peachy
drove it no problems, I went to work , then left it 8 hours and drove it home again no problems
I left it 9 hours went to work , left it 8 hours, again no problems,
drove to garage , parked up, left it 15 ish minutes fired it up , BANG errors,
hmm, coincidence?

Steve

Get a voltmeter and tell us what the battery voltage is. Could be that all that driving and the alternator working sporadically is not keeping the battery up to charge so the battery charge could be low.