Trans Fail Safe Message, EKM Code 60

[bmw528e11]

'95 840ci M60 5HP30, When Turning Ignition On, Transmission Gear Designated screen on cluster is Blanked, and after engine is started, OBC has a trans fail safe message..
DME and EGS does not Have any codes.
EKM has a code 60 Data Lina to EGS disturbed.. (only sets that code after engine started..)

Note: No drivability issues, transmission upshifts and down shifts with no issues..

Did check the wire From EKM X39 Pin 10 to EGS Pin 25, No shorts to B+ or ground.. 0.5ohms..
M60 Transmission.png

Any help would be appreciated!
Thank you!

[Timm]

Check F12 - it supplies current to the gearbox selector switch. Without power the display reverts to being blank. As you have diagnostics working you can check the output from the switch - more information here:

http://www.meeknet.co.uk/e31/timms_b...e_problems.htm

http://www.meeknet.co.uk/e31/Timms_B...use_Finder.htm

[bmw528e11]

Check F12 - it supplies current to the gearbox selector switch. Without power the display reverts to being blank. As you have diagnostics working you can check the output from the switch - more information here:

http://www.meeknet.co.uk/e31/timms_b...e_problems.htm

http://www.meeknet.co.uk/e31/Timms_B...use_Finder.htm

Thank you Tim, I do have power to my safety switch, and I do have an inputs to EKM and EGS from the safety switch, except when switching from P-R-N-D-4-3-2 EGS with live data does recognize the shifter. But! the EKM on the other hand didn't recognize ?-2-?-D-4-3-R
Now, I did check the EKM shifter input voltage, I do receive 12volts through wiring coming from shifter, when ever I shift through gears.. the shifter safety switch, IS just a regular ON & OFF switch.. so, according to wire diagram the results do correspond, but for some reason EKM in live data doesn't..

Now Eedegree, did mentioned this in different thread.

When the capacitors fail, the localized power supply for the microcomputer is not a clean regulated supply. At some point the module does a brownout (likely with a high current thing switched on) and all bets are off.. The RAM gets corrupted, maybe the program counter gets reset, stack overflow (what little stack a 1MHZ CPU has), etc.. The CPU may then jump to a programming vector, or might try to log a fault to the (1kilobit=128 bytes) EEPROM at wrong address (a configuration section instead of a logging section) and bam, the car now thinks it should expect the wiper pressure relay, headlight washers, etc.. (note, this would have nothing to do with the capacitor repair, since the EPROM would have been corrupted prior to the fix)

Another possible problem is that the Serial EEPROM could be bad.. a 1K EEPROM is only 128 bytes, but they only have limited write/erase cycles, on the order of ~10000. A 'regular', recurring fault could cause an EEPROM to fail, and then the coding (and faults) wouldn't be saved properly, and it only takes 1 lazy bit to code in an option that doesn't exist..

Some info on the vehicle.. vehicle had rough running condition which included, a huge misfire on all cylinders, vacuum leak, mixed O2s (one of them switched signal with ground wire pins) and I see someone replaced a MAF.

After sorting thing back to it's original designation , vehicle DOES NOT misfire, and drives perfectly fine! No hesitation on acceleration, no rough upshifting or downshifting..

Everytime I went through an ignition cycle, I would see the E P on the cluster, but would disappear within a second, and a "trans fail safe" message on OBC to follow..

I did check the wiring between 'shifter and EKM & EGS' and a Bus signal from EKM to EGS - which was from 1.*V -12.*V signal, (which include 5 waves with 0.5 second apart, then 1.5 seconds just plane 12v and the 5waves with 0.5 second)

So, I thought, maybe it did wrote that message into EKMs EEPROM, so I did disconnect batteries over night. Next morning loaded tested both batteries (both pass) charged them, connected back to the vehicle and still no change, E P in cluster would stay on for a second, then would just go in blank, and transfail safe message in OBC..

Now, I tried to /basic?/ code EKM.. after just going through coding procedure, my E P doesn't pop out on key cycle.. but the trans fail message will pop out on OBC only after engine would start..

And That's where I stopped... Customer is more then happy to see it run properly.. (but it's just annoying trans fail ding, Everytime engine starts up.) Sad or happy, but that message does not effect vehicle's drivability...

[bmw528e11]

2000 and newer Mercedes have issue is the code persisted for sometime without a repair, the code locks into the module, and can't be erased, unless the module would be recoded or go through "reset control unit"..

[Timm]

As your gearbox is still operating correctly - despite the error codes I would guess that the EGS has decided it has a shift-lock solenoid - we have seen this happen a few times now and gives exactly the behavior you report. You initially get the gear display, then get a TRAN FAIL-SAFE PROG but the gears all work correctly.

[bmw528e11]

despite the error codes I would guess that the EGS has decided it has a shift-lock solenoid - we have seen this happen a few times now and gives exactly the behavior you report. You initially get the gear display, then get a TRAN FAIL-SAFE PROG but the gears all work correctly.

But wouldn't it set a code for a shift-lock solenoid?

[Timm]

Yes, hence the qualifier! I can't think of any other error that throws up TRANS FAIL-SAFE PROG but allows the gearbox to work correctly. Also, the error should raise an EGS error code......

[bmw528e11]

Yes, hence the qualifier! I can't think of any other error that throws up TRANS FAIL-SAFE PROG but allows the gearbox to work correctly. Also, the error should raise an EGS error code......

Thats what I'm assuming, since the transmission had malfunction for too long, EKM got that code 60 'hard' stored it.. Well.. customer needed his vehicle, he couldn't wait any longer..

[dragon850]

bmw528e11 great job on troubleshooting!