HELP! SMG can't select reverse.

[paul_325i]

Hi guys.The SMG transmission in my 2002 e46 325i won't select reverse gear. All the forward gears function normally and there is no warning lights to indicate any problem. I suspect this may be an electrical issue but if any of you guys on the forum have an idea what the cause of the problem may be or if anyone has experienced this before then I would be most interested to hear from you. Any help would be great.Many thanks... Cheers.

 

[initialM]

Calling SMG expert bro B33mer:top:

 

[B33mEr]

I haven't encountered this problem yet bro ... but i think you're right it could be electrical issues could be a bad wiring connection or even could be you relay fuse. Only way to find out is to send it to a good workshop that are familiar with SMG/SSG. Hopefully other sifu's or guru's here will be able to shed some light on this.

p/s: having said that please check your hydraulic actuator pump for leaks cos most of the times that's the culprit of most SSG failure/problems.

 

[B33mEr]

Calling SMG expert bro B33mer:top:

Hehehe me no SMG expert ... me only expert on my car je bro :love: anything else i'm still on the learning curve ... d real SMG sifu's and guru's are hiding somewhere

 

[leforte]

Dont think its electrical related. If its a electrical glitch or fault or even if there is a lost of hydraulic pressure at any of the 2 gear actuators, the obd would have highlighted it. if its leaking fluid, a simple check at your smg fluid reservoir is all it takes to diagnos it.

let me guess, you select reverse and gear indicator shows that you are in gear, however the car doesnt move and the engine just goes up in rev? any other issues prior to this with any other gears ie:- popping out of gears?

chances are, your reverse gear selector rod is gone and its a early warning that you may required a full transmission overhaul soon before you start missing all the other gears and further damage the other transmission parts. a replacement with a updated manual transmission repair kit from bmw is required. this is a well known defect of the manual getrag gearbox across the entore bmw range.

just in case you need to know, the repair kit and installation doesnt cost much, if you are due for a clutch replacement, you may do it at the same time to safe on the labour.

 

[rts_4]

Dear Paul,

I had almost similar problem back in 06 but my smg only had difficulties to engaged to R especially at cold start. AB checked the problem and said that there were some leaking coming from the GB and wet the clutch. They charged me almost 400 to remove and reinstall the gearbox and to fix the problem.

Regards,

 

[ozone]

There was once or twice from cold start and I pushed it to reverse but the dashport read as N. But as soon as I push it back to N and then to R again it works. Hope it is not sign of your problem to come

 

[paul_325i]

Many thanks for the response guys.

Leforte: When I move the gear selector to 'R' while pressing the foot brake it sounds like, from the outside, that the gearbox is actually engaging reverse. Unfortunately the gear position light on the dash remains showing 'N' and the car goes nowhere in reverse. All 5 forward gears function normally. I have tried the recommended SMG reset of driving the car forward at 80km/hr then selecting 'N' and pulling & holding both steering wheel paddles back for 5 seconds. Unfortunately this did nothing to reset the reverse but seems to have improved the forward gear changes. The clutch and at least 1 of the actuators have been recently replaced and there are no fluid leaks showing under the car.

For other SMG owners: I have found information on the web that this 'no-reverse' problem is a common issue with the SMG. I have made enquiries with some websites for advice and will post any info I get here for other SMG owners to benefit.

Believe it or not I also found a U.S. based website dedicated to BMW owners experiencing the 'no-reverse' problem: 'www.noreverse.org' Most of the issues on this site are with the earlier 2000 323i sedans with auto transmission. There is an astounding number of reported cases posted here. Owners beware!

Cheers to all.

 

[B33mEr]

Many thanks for the response guys.

Leforte: When I move the gear selector to 'R' while pressing the foot brake it sounds like, from the outside, that the gearbox is actually engaging reverse. Unfortunately the gear position light on the dash remains showing 'N' and the car goes nowhere in reverse. All 5 forward gears function normally. I have tried the recommended SMG reset of driving the car forward at 80km/hr then selecting 'N' and pulling & holding both steering wheel paddles back for 5 seconds. Unfortunately this did nothing to reset the reverse but seems to have improved the forward gear changes. The clutch and at least 1 of the actuators have been recently replaced and there are no fluid leaks showing under the car.

For other SMG owners: I have found information on the web that this 'no-reverse' problem is a common issue with the SMG. I have made enquiries with some websites for advice and will post any info I get here for other SMG owners to benefit.

Believe it or not I also found a U.S. based website dedicated to BMW owners experiencing the 'no-reverse' problem: 'www.noreverse.org' Most of the issues on this site are with the earlier 2000 323i sedans with auto transmission. There is an astounding number of reported cases posted here. Owners beware!

Cheers to all.

I assume that when you replaced the clutch and actuators you have done a software update for your DME and smg controller?

 

[paul_325i]

Hi B33mEr,

Program and encode for the DME was performed quite a long time ago at 45,000kms. After talking with one of the other forum members I'm reasonably confident now the problem with my SMG not engaging reverse is a software issue. Since this problem started the car has surprisingly engaged reverse a couple of times. I have the car booked into the Brunei BMW service centre next week for a software update. Thanks for your advice bro.

By the way any other readers who have experienced or heard of this problem I would be very interested to hear from.

Cheers.

 

[YellowMellow]

hope they can solve your problem bro..

 

[leforte]

Many thanks for the response guys.

Leforte: When I move the gear selector to 'R' while pressing the foot brake it sounds like, from the outside, that the gearbox is actually engaging reverse. Unfortunately the gear position light on the dash remains showing 'N' and the car goes nowhere in reverse. All 5 forward gears function normally. I have tried the recommended SMG reset of driving the car forward at 80km/hr then selecting 'N' and pulling & holding both steering wheel paddles back for 5 seconds. Unfortunately this did nothing to reset the reverse but seems to have improved the forward gear changes. The clutch and at least 1 of the actuators have been recently replaced and there are no fluid leaks showing under the car.

For other SMG owners: I have found information on the web that this 'no-reverse' problem is a common issue with the SMG. I have made enquiries with some websites for advice and will post any info I get here for other SMG owners to benefit.

Believe it or not I also found a U.S. based website dedicated to BMW owners experiencing the 'no-reverse' problem: 'www.noreverse.org' Most of the issues on this site are with the earlier 2000 323i sedans with auto transmission. There is an astounding number of reported cases posted here. Owners beware!

Cheers to all.

paul,

the noreverse.org website is for all bmw fitted with the ZF 5hp19 STEPTRONIC gearbox. yours is a getrag 5speed MANUAL with smg factory retrofit. so it bares no resemblance or relations to you current issues.

the process you mentioned at the first paragraph has no effects on your no reverse issue either . that is a smg slip detection process, and its only required or done after a tire change or wheel change. this process also resets the clutch engagement point after all the wear and tear.

if its software problem, swapping in a new or borrowed smg egs unit will quickly diagnos the issue. which in your case is definately not.

have your bmw speciallist check on the gear selection assembly. that's your problem, and you need a getrag repair kit for it. your bmw speciallist can easily find the tecnical buletin from the TIS manual and all the updated parts or repair kit is clearly stated in the parts catalogue. its a inherited getrag gearbox failing point and it traces itself back to all bmw car fitted with a getrag unit.

 

[YellowMellow]

paul,

the noreverse.org website is for all bmw fitted with the ZF 5hp19 STEPTRONIC gearbox. yours is a getrag 5speed MANUAL with smg factory retrofit. so it bares no resemblance or relations to you current issues.

the process you mentioned at the first paragraph has no effects on your no reverse issue either . that is a smg slip detection process, and its only required or done after a tire change or wheel change. this process also resets the clutch engagement point after all the wear and tear.

if its software problem, swapping in a new or borrowed smg egs unit will quickly diagnos the issue. which in your case is definately not.

have your bmw speciallist check on the gear selection assembly. that's your problem, and you need a getrag repair kit for it. your bmw speciallist can easily find the tecnical buletin from the TIS manual and all the updated parts or repair kit is clearly stated in the parts catalogue. its a inherited getrag gearbox failing point and it traces itself back to all bmw car fitted with a getrag unit.

FYI:

paul's ride is fitted with Magneti Marelli gearbox and ECU. And Magneti Marelli repair kit will cost him around RM18K. Brand new gearbox around RM26K with 2 years unlimited milaege warranty. Magneti Marelli ECU around RM4.7K huh..

let him re-program his gearbox next week and we see how it goes.

my 2 cent..

YM

 

[leforte]

FYI:

paul's ride is fitted with Magneti Marelli gearbox and ECU. And Magneti Marelli repair kit will cost him around RM18K. Brand new gearbox around RM26K with 2 years unlimited milaege warranty. Magneti Marelli ECU around RM4.7K huh..

let him re-program his gearbox next week and we see how it goes.

my 2 cent..

YM

magneti marelli gearbox should be a SSG not a smg then.

the title should be change to SSG cant select reverse.

 

[YellowMellow]

magneti marelli gearbox should be a SSG not a smg then.

the title should be change to SSG cant select reverse.

Youre rite bro leforte. Should be SSG not SMG. But we in Msia boleh call it SMG la..:wink:

 

[B33mEr]

magneti marelli gearbox should be a SSG not a smg then.

the title should be change to SSG cant select reverse.

Please note that it was called SSG later BMW change it to SMG ... so the OP got it right 1st time.
The gearbox is a standard BMW manual gearbox ONLY the SMG controller and the hydraulic actuator system is made by Magneti Marelli.

SMG/SSG = non ///M e46 and Z4 cars
SMG1 = E36 ///M3 Euro (Siemens)
SMG2 = E46 M3 (Siemens and ///M division of BMW)

 

[leforte]

its still a ssg by any name you called it. it works differently and the hardware is entirely differen. stupid bmw ag. confusing the masses. sigh....

beemer, the ssg gearbox is made by MM as well. and it was never a standalone manual unit from the start. unlike previous smg boxes which is basically a manual getrag unit with retrofited smg controls.

 

[YellowMellow]

its still a ssg by any name you called it. it works differently and the hardware is entirely differen. stupid bmw ag. confusing the masses. sigh....

beemer, the ssg gearbox is made by MM as well. and it was never a standalone manual unit from the start. unlike previous smg boxes which is basically a manual getrag unit with retrofited smg controls.

again youre rite bro.. :top:

 

[B33mEr]

its still a ssg by any name you called it. it works differently and the hardware is entirely differen. stupid bmw ag. confusing the masses. sigh....

beemer, the ssg gearbox is made by MM as well. and it was never a standalone manual unit from the start. unlike previous smg boxes which is basically a manual getrag unit with retrofited smg controls.

again youre rite bro.. :top:

Logically it wouldn't make much economic sense to have a small niche volume of SMG gearbox rather than have a mass volume gearbox and adapted to a electronically controlled hydraulic actuated system cos it would be too expensive. If that was the case then SMG or SSG wouldn't be so problematic mate .... Mine is a 5 speed getrag unit GS5S31BZ according to realoem.com

Also i've been searching for a magnetti marelli gearbox for BMW ... it seems that i can't find it ...
http://www.magnetimarelli.com/english/powertrain_prodotti.php

An "excerpt" from MM website
TRASMISSION CONTROL

Magneti Marelli Powertrain produces robotized transmission gear or AMT (Automated Manual Transmission), that consist of the transformation of a regular gear box where the manual transmission is replaced by an Actuation kit (plug-in) electronically controlled by a Transmission Control Unit (TCU)

This system allows:

* Automatic gear shift
* Automatic clutch

In this way the driver has the following options:

*
Possibility to choose between manual or automatic transmission
*
Manual transmission by joystick or at the wheel
*
No more clutch pedal

In addition all the information can be displayed on the dash board for a deeper awareness of the driver.
-------------------------------------------------------------------------------

Again i cant find any mention of gearbox (if any) made by magnetti marelli for BMW except for the electronic transmission control or AMT .
Even M3 SMG2 uses the same gearbox as found on the regular manual M3 ... i didn't know Siemens made gearbox too

Anyway here's an excerpt from BMW pdf document explaining SMG for their technical staff

System Components
The SMG II system is consists of the following components:
• Basic Gearbox (S6S420G, Getrag type D)
• SMG II Control Unit (Siemens)
• SMG CAN Bus
• DME Control Unit (MSS54)
• Hydraulic unit and solenoids
• Gearbox Actuator
• Clutch Slave Cylinder with PLCD (Permanent Linear Contactless Displacement)
• Shift Lever Module with Shift Lock
• Steering Wheel Paddle mounted switches
• DRIVELOGIC Control
• Display in instrument cluster
• DSC control unit
• SAC dry single disc clutch

 

[leforte]

Quote from beemer's post.

...Mine is a 5 speed getrag unit GS5S31BZ according to realoem.com

If yours is a getrag unit, the unit should be a S5D250G, the shifting pedals are PULL only on either left or right to shift. GS5S31BZ is a 5speed Magnetti Marelli unit. this is a SSG equipped model. the shifting can be done via pulling/pushing on either pedal. what is yours?

...M3 SMG2 uses the same gearbox as found on the regular manual M3 ... i didn't know Siemens made gearbox too

M3 uses the getrag S6S420G unit which is also use in the smg equipped cars. this gearbox is also used in the e46 manual m3, euro e36 m3 evo, e34&e39 540i manual 6speed cars.

siemens dont make any gearboxes but they make and supply the smg control unit (EGS)