EGS & TRS ZF6HP26

Mistermorgan · #1 10-07-2021, 08:13 AM

I am am hoping someone could help me understand what is possible with my EGS & Transmission range sensor on my x5 4.8is

I have a ZF6HP26 box on the car, I have had some intermittent issues with a complete non-start, not cranking nothing, It will also throw up an EGS signal line disturbed error code as well as speed with the non start. I have determined it is likely an issue with the TRS, it feels like the car doesn't know its in neutral/park and blocks the start.

I recently serviced the transmission and when I took out the valve body there was a good coating of metallic paste around the transmission switch slider which I cleaned but the issue persists. The TRS is integrated into the EGS which in turn is integrated into the valve body on this transmission.

Q1 - Can these electronic components actually be rebuilt, I have seen you can buy the PCB for the range switch online bit not found any guidance on how the switch is rebuilt then re-sealed to sit in the oil pan again
Q2 - if I need to replace the EGS and range switch as a whole, can this actually be done, again I've seen the whole mechatronic unit available to purchase but a local transmission shop told me its not possible as a donor unit cant be coded so would need a whole new valve body & Mechatronic unit from ZF. - this doesn't sound right to me. There is a tesla in orbit, anything is possible right
Q3 - Failing all of this, is there a coding option to bypass the neutral safety switch - I would be keen on doing this as a temporary solution to actually confirm its the TRS that's causing the issue.

As llways thanks for any guidance on this

Sponsored Links

andrewwynn · #2 10-07-2021, 11:00 AM

I thought my range switch was at fault. All symptoms pointed to it.

I was about to pull the bottom off my trans to dig out the switch (3.0 motors the switch is inisde) when it was suggested to look into the main connector on the back of the transmission.

Sure enough it was filled with rusty water shorting out the pins and giving literally random positions of the gear box.

(My dash literally told me I was in 54th gear at one point).

Check your connections from transmission to EGS box.

The wiring can go bad on the harness on the inisde and one other failure I've seen is when transmission is put together, the harness socket was not installed correctly and was inset too deep for the connector to reach all the pins.

Reading live data from the transmission I would get completely bizarre results from L1-L4 that was the key. I was thinking that had to be the position switch is dead, turned out to be rusty water in the connector.

Mistermorgan · #3 10-07-2021, 04:30 PM

Thanks Andrew,

I would love to see the differences between the connectors on these models. I have a single connection which has no wiring inside the trans, the mechatronic sits inside the oil pan and the sleeve hosts its connection to the harness outside the trans. I initially thought this was the culprit, pulled the connector off, cleaned it and changed the sleeve which had a few o-rings to keep the oil in and water out.

Was your water in the connection at the transmission or elsewhere?

Just another note I also replaced the ignition switch to rule that out, I can only assume at this point it’s the internal range switch slider/pcb

crystalworks · #4 10-07-2021, 04:46 PM

Yes, he's talking about intrusion into the mechatronic sleeve connector.

AFAIK it's possible to recode the VIN to a used EGS. Or at least I thought it was possible by using a combination of WinKFP, INPA, and NCSExpert.

Edit: This isn't the best thread, but confirms the procedure seems at least possible. https://www.bimmerforums.com/forum/s...used-TCM-(EGS)

andrewwynn · #5 10-07-2021, 05:07 PM

Can you read the signals from the egs to see about the intermittent issue. Maybe you can see like I did L values that make no sense that like you suggested won't allow a start.

Have you tried starting in N vs. P ?

Mistermorgan · #6 10-07-2021, 05:09 PM

Thanks for the info good to know it can be flashed/paired with the DME

I am reluctant to buy a second hand unit and have the same problems, hoping someone might have experience with flashing a new or rebuilt unit. Do we think this would be the same? Assuming I would just have to pay close attention to make sure the part numbers and hardware numbers match my existing? Given these trannies were in SO many different manufacturer vehicles I’m guessing I can’t use a TCM from a 6hp26 out of a land rover for example?

My unit is a Bosch 7557063 control unit GS19

Mistermorgan · #7 10-07-2021, 05:13 PM

Hey Andrew,

I can normally read signals and the range sensor is fine, I can check on gear lever position in ista and it results as expected. However when I do get the no start issue I get no comms with the EGS at all, then after waiting some time it can start and has the error memory for egs signal line disturbed, it’s really intermittent. Like it will be fine for a few months then all of a sudden it’s back and happens once a week before going away again. The car isn’t driven regularly so it would probably be more common if it were a daily driver.

andrewwynn · #8 10-07-2021, 05:19 PM

The "straight read" is there is a broken wire that connects most of the time. Are there any connections you haven't taken apart and cleaned?

One guy on the forum did have a problem where the connector from inisde wasn't set correctly (too far in) and it worked intermittently.

FYI the problem with mine is water comes in through the wire jacket and fills the plug from the inisde. Make sure that is not the case dirt you even if you cleaned it out.

My Spidey senses say the problem is internal for you. Also if It was the range switch you would get funky reading like gear 54 like me not "can't communicate".

Mistermorgan · #9 10-17-2021, 09:27 PM

Thanks for input here guys - I've just dropped it at my local indy, he also suspects it's a faulty EGS module but will find out more tomorrow. I have a lot of codes coming from the EGS now

51 A7 No Message (engine speed), receiver EGS, transmitter DME-DDE
51 AD No message, receiver EGS, transmitter DSC

Also the intermittently present IKE: EGS signal line disturbed

I've seen companies offering a remanufactured and coded EGS module for these like this one https://www.precisionecu.com/product...amming-service - which is advertised as plug and play no coding required which makes me think I can buy a remanufactured module and program myself.

I can get a new one, not coded for around $400 AUD so I'm tempted to give it a go and see what happens

ati17 · #10 03-14-2023, 10:39 AM

Hello, maybe here I can find hep.
the problem appeared after the repair of the engine. The gearbox got into emergency mode and the speeds were not displayed on the screen (P R N D). Next, they replaced the TCU board, which is on mechatronics and registered using a computer. I thought everything was fine, but in the morning I started it and tried it in manual mode, everything works. After a while the manual mode stopped working. Always in the morning, the manual mode works, and a little (according to my observations) later, when the gearbox warms up, manual mode stops working. But it stops strange, it doesn’t switch speeds up, but down if you pull the lever towards the minus, it shows the speed either 3 or 2 which at that moment. If I turn on the manual mode from the place, then it turns on 1 but does not switch up further. All this after some time after the start of the movement. In the morning on a cold one, it works both up and down. I also noticed a problem, when you put it in R mode, the diagnostic connection with the box is lost. What can you advise where to start? Thank you
PS. at the time of the problem, I changed the oil about 7000 km ago
Auto 2006 year BMW E83 3.0 diesel gearbox ZF6HP26

Sponsored Links