Trans failsafe Program

[Kasxx]

Was getting the following lights:
ABS, Brake, Service Engine soon, traction control(triangle in center) on start,
then after traveling the "trans failsafe program" would come on.
took vehicle to import mechanic diagnosis was:
ABS sys:
3A(No message from EGS(trans control module) control unit
5A(Breif Power Interupption)
5E(rotation-rate Sensor, self test

Trans sys:
130 CAN timeout ASC
128 Monitoring, CAN bus
032 Speed signal output

Engine Sys:
P0600 Serial communication link

He serviced and check the ABS/DSC, ECU/DME and TCM modules.
Reset Computers
He did 5 drive cycles in vehicle
all clear
picked it up this afternoon, drove fine. then tonight after driving awhile the same symptoms came up. This occurred after dark and my wife had the headlights on(not sure if this could have anything to do with it.)

Any thoughts are much appreciated.

[HEISING]

Possibily the alternator has excessive ripple or it's just weak. Drive around with a dmm connected to the + post under the hood and monitor the DC voltage ( have a passenger do the monitoring) Turn on excessories and see if it falls to low.

Good Luck

[Kasxx]

okay so last night i left the neg battery cable off. to clear

so this morning reconnect and start up abs/brake lights on, also service engine soon light on, but when i backed up out of driveway the ABS and Brake light went away.
Drove about 2-3 miles runs fine
back home, turn off and restart and the brake and abs lights on and then the gauges all drop, (rpm, temp). when i put into revesre and then i get the "Trans Failsafe Program"

[imsello]

probably a bad abs sensor. that in most cases causes all the other lights to gon as well. it happened to me in my 528i. i changed the abs sensor and all the other lights never came on again

[Turbo_Bimmer]

Originally Posted by Kasxx

okay so last night i left the neg battery cable off. to clear

so this morning reconnect and start up abs/brake lights on, also service engine soon light on, but when i backed up out of driveway the ABS and Brake light went away.
Drove about 2-3 miles runs fine
back home, turn off and restart and the brake and abs lights on and then the gauges all drop, (rpm, temp). when i put into revesre and then i get the "Trans Failsafe Program"

Kasxx, the problem of ABS, parking brake, rpm, temp gauge could be a couple of things, but what got my attention is the fact that you have communication errors between modules (CAN timeout).
I got this exact same problem with my E46 (exept for the transmission, mine is manual).
Look on a thread I wrote here, it may help you or your mechanic find the problem:
SOLVED: DSC, ABS, parking brake light ON - E46Fanatics

[Kasxx]

Okay mechanic says, the only code pulling now is the trans sys:lose of signal(something like that)

he checked the alternator and under NO LOAD)everything off like AC, radio and such.

voltage is fluctuating, up and down 1-2 volts, said the manufacturer says in general the voltage can be in the range of 10-15V.

[Kasxx]

cost to replace alternator is $1200 with the mechanic

i have found bosch alternator for this vehicle for 400 at autozone/oreilly

I have worked on my vehicles (not BMW's) all my life, so im very experienced at changing parts . In looking it up on how to change the part, it seems rather simple, remove fan cowl, remove alt. bolts, etc... just like most other alternators.

trying to decide if that is something i should do, guess im just a little intimidated by the BMW NAME. This is my first one.

[HEISING]

Originally Posted by Kasxx

Okay mechanic says, the only code pulling now is the trans sys:lose of signal(something like that)

he checked the alternator and under NO LOAD)everything off like AC, radio and such.

voltage is fluctuating, up and down 1-2 volts, said the manufacturer says in general the voltage can be in the range of 10-15V.

Time to find a different Mechanic. Try over 13 Volts all the time when the engine is running. The BMW won't run at 10 Volts.

[sasquatch]

Voltage should not drop below 13.2V when the engine is running and the alternator/battery are working correctly. If it is that points to a failing alternator or rectifying circuit.

If I remember correctly the pre-facelift models had water cooled alternators. Not sure what is involved but it is not like replacing a Chevy 350 alternator. More involved.

[Jordo]

Originally Posted by Kasxx

Okay mechanic says, the only code pulling now is the trans sys:lose of signal(something like that)

he checked the alternator and under NO LOAD)everything off like AC, radio and such.

voltage is fluctuating, up and down 1-2 volts, said the manufacturer says in general the voltage can be in the range of 10-15V.

Like he said.... Your mechanic is a rookie at best. But on a good note, if he did take accurate readings, this would definitely give you symptoms that you described.