EGS Transmission failsafe mode and INPA error

[sklingler93]

My 2001 740i (e38) started giving a "Transmission Failsafe Program" error after reseating the engine wire harness while replacing some gaskets. The dealer told me I had a bad EGS, claiming they were not able to connect to any module in the car when the EGS was plugged in, and quoted me $1500 for a new one. I bought a salvage unit instead.

I know you have to code the module to the vin. Without the EGS plugged in, I can use INPA to connect to the ECU and other modules properly. However, even with the new (salvaged) EGS plugged in INPA cannot connect to any module. I tried a second salvage EGS with the same results.

Has anyone seen this sort of thing, or could point me in the right direction? Thanks!

[bmwdirtracer]

You have a BUS problem. Plugging in the EGS is dragging down the bus line, preventing communication. This doesn't always have to be the fault of the computer (EGS) itself....it can be the PLUG....OR, it can be the plug at the transmission. Note that Mercedes cars of this era and for another half dozen years had plugs at the transmission which leaked fluid into the electrical plug. The problem was SO bad in these vehicles, that the fluid pumped all the way up to the computer, through the electrical harness. BMWs don't have this issue THAT badly, but certainly, if you've got a short in either plug, you stand the chance of dragging down the BUS line, which connects many of the computers. Undo the connector at the transmission itself: do you see oil there? Get yourself a can of electrical contact cleaner (Wurth Electrical Contact Cleaner OIL is the very best !), and clean the electrical plugs (both sides) at the transmission, and at the EGS. Also, make sure that the E-Box is DRY, no green residue in the bottom, and that the 10mm nut outside the e-box, and very nearby, is tight, and has a clean connection.

BUS line wires are twisted together in pairs, generally.

[stvsxm]

You have a BUS problem. Plugging in the EGS is dragging down the bus line, preventing communication. This doesn't always have to be the fault of the computer (EGS) itself....it can be the PLUG....OR, it can be the plug at the transmission. Note that Mercedes cars of this era and for another half dozen years had plugs at the transmission which leaked fluid into the electrical plug. The problem was SO bad in these vehicles, that the fluid pumped all the way up to the computer, through the electrical harness. BMWs don't have this issue THAT badly, but certainly, if you've got a short in either plug, you stand the chance of dragging down the BUS line, which connects many of the computers. Undo the connector at the transmission itself: do you see oil there? Get yourself a can of electrical contact cleaner (Wurth Electrical Contact Cleaner OIL is the very best !), and clean the electrical plugs (both sides) at the transmission, and at the EGS. Also, make sure that the E-Box is DRY, no green residue in the bottom, and that the 10mm nut outside the e-box, and very nearby, is tight, and has a clean connection.

BUS line wires are twisted together in pairs, generally.

chris, if these connectors are the multi fine pin mil-spec type, then if they are a little weird going in, it can force one or more of the pins down inside its own half and therefore never connect. have a close look and see if all the pins and all the sockets are at the same heights in their respective halves...

[bmwdirtracer]

You make an excellent point, Steve.

And it works the opposite way, too: I have an X5 at work right now that has no stereo sound or lighting....but it has static. I fought to unplug the amplifier, knowing what I was going to find: a green female plug, with some green pins from the male side, sticking out of the female connector. Unfortunately, that's a ~40 pin connector, and I'm going to have to splice every wire to the plug. I'm glad I'm very good at wiring.......(The Amp with plug and a foot of wiring is on the way)

[sklingler93]

Thank you so much for your input and quick responses bmwdirtracer and stvsxm. I cleaned the connectors and verified that they are all in good shape, yet the problem persists.

I did realize that the salvage EGS units I purchased are for the non-sport e38 and don't match the original zb number of 7508398, instead they are 7508396. Could this be a cause of diagnostic bus failure?

[328 Power 04]

Thank you so much for your input and quick responses bmwdirtracer and stvsxm. I cleaned the connectors and verified that they are all in good shape, yet the problem persists.

I did realize that the salvage EGS units I purchased are for the non-sport e38 and don't match the original zb number of 7508398, instead they are 7508396. Could this be a cause of diagnostic bus failure?

No, that would not be a cause. They are both GS8.60.2 modules, and pinouts would be the same.

[Mayorchuck]

Agreed, that would not cause a bus issue. If it were mine, I would pull the plugs on the DME (ECU) to check for corrosion as it talks to the TCM via the Can bus in the 24 pin black connector. The diagnostic signal is on a pin in that connector as well. As suggested, I would also check the connection on the transmission itself.

Diagnosis on CAN-Bus

Causes

The failure of communication on the CAN-bus (i.e. fault code entries relating to bus communication in the individual control modules may be caused by the following:
- Breaks in line (open circuits) or short-circuits in the communication lines
- Interference voltages in the vehicle electrical system caused for instance by defective ignition coils or ground connections
- Failure of the communication modules in the individual control modules
- Failure of the voltage supply of individual control modules (a battery voltage decreasing gradually when the battery is almost discharged can also lead to fault code entries as not all control modules switch off simultaneously due to the voltages supply being too low).
Terminal resistors

A 120 Ohm terminal resistor is installed in each of two control modules of the CAN network between the communication lines CAN-H and CAN-L. A resistance of 60 Ohm (parallel connection) can therefore be measured between the two communication lines in the control module network. The lines can be checked easily by measuring the resistance with an adapter at one of the control modules. When disconnected the resistances of both control modules can be measured directly. Control modules without terminal resistors normally show a value from 10 kOhm to 50 kOhm. The terminal resistors are accommodated in the ASC/DSC control module and, depending on the type of engine, either in the instrument cluster or in the engine management.
Cause

Failure of a control module or communication module normally triggers a fault code entry in the other control modules connected to the CAN-bus.
Under certain circumstances, failure of a communication module in the control module may paralyze the entire CAN-bus. Faults in communication with all other control modules are entered in all control modules connected to the CAN-bus.


A6000 Engine control module (DME)

Connector overview

Number	X-pin, color	Description
X60001	9-pin, black	Connector Engine control module (DME) Module 1
X60002	24-pin, black	Connector Engine control module (DME) Module 2
X60003	52-pin, black	Connector Engine control module (DME) Module 3
X60004	40-pin, black	Connector Engine control module (DME) Module 4
X60005	9-pin, black	Connector Engine control module (DME) Module 5

Pin assignments at connector X60001

Pin	Type	Description / Signal type	Connection / Measuring notes
1		Not used
2		Not used
3		Not used
4	M	Ground	Ground connector X6460
5	M	Ground	Ground connector X6460
6	M	Ground	Ground connector X6460
7	E	Terminal 30 voltage supply	Fuse F4
8	E	Terminal 87	Fuse F1
9		Not used

Pin assignments at connector X60002

Pin	Type	Description / Signal type	Connection / Measuring notes
1	M	Heated oxygen sensor ground	Heated oxygen sensor II behind catalytic converter
2		Not used
3	E/A	CAN-bus low	AGS transmission control module
4	E/A	CAN-bus high	AGS transmission control module
5		Not used
6	E/A	Diagnosis signal TXD	Splice, TXD X6866
7	M	Heated oxygen sensor ground	Heated oxygen sensor I behind catalytic converter

[stvsxm]

with respect to all that have contributed the extensive electronic diagnosis here, isn't the telling sentence in the original post " I reseated the connector after the gasket change " ? so doesn't that mean the module was ok before he unplugged it and is now, suddenly bad after he plugged it back in ? isn't this a case of " the last thing you touched " ? he unplugs a working device.. plugs it back in... no function anymore . subsequent devices... no function... isn't the only conclusion that he damaged the plug or wiring somehow ?

[bmwdirtracer]

That's why I was mentioning the plugs, and the 10mm nutted ground wire outside the E-box. Still, I admit to losing focus....must have been that third beer.

[Mayorchuck]

We don't know what 'harness' he unplugged or what gasket he changed. This car has an issue with water or coolant working up the loom and coming to rest in the DME connectors causing various issues. So without detailed info, I was just suggesting something we see in the E38 forum. Need more specifics from OP.

[stvsxm]

don't misunderstand... im not saying you are wrong in any respect... all im saying is that I am immediately suspect when someone says... " it worked before I touched it and now it doesn't " . those situations are almost always " pilot error" not some pre existing issue... I once asked my roommate (a computer guy ) at college why my printer stopped working and he started in on an explanation having to do with planetary gravity and a polarity shift in the universe as opposed to the cable that had fallen out of the back which was really the issue... all im saying is that a lot of times its the simplest and most obvious thing... like something you did wrong on the last thing that you touched.