ADS vs OBDII question

[TerraPhantm]

Okay so I know on E36 and older cars (and possibly E39s and E38s too) you need an ADS interface to access all the modules... My question is - which modules *don't* require the ADS interface? Just curious to know what I can and can't do if I try connecting to an E36

Sorry if the information is already out there, I tried searching and couldn't come up with anything.

[David Mc]

I have connected to quite a few 4 & 6 cylinder E36's and an E38 and the answer seems to vary quite a bit between year and engine combinations. Some cars will not show DME or DDE connections and ABS/EGS.
The BMW Electrical Troubleshooting Manual for my E36 shows pin 15 (L line connection) to the DDE on DDE 2 cars and DME of the 316i, 318i and 318is as well as the EGS of 4 and 5 speed diesel cars and the EGS of 4 speed 4 cylinder models, but I am also unable to access ABS data without ADS functionality. Since the L data line is RXD as opposed to the pin 17 and 20 K data lines, which are TXD, I suspect that if signals are not conveyed by pin 15, other interconnected modules are not woken up and so do not respond.
In light of the hit and miss nature of the results when attempting to diagnose ADS compliant cars with an OBD interface, I now only use the interface mode appropriate to the vehicle on which I am working.

[IcemanBHE]

It does seem hit or miss. Pretty much the guideline I use is that anything MY 95 and less (inc all E36 and Z3) will be ADS.

However, have seen some 96MY E38 750 V12s that were ADS.

This is why Im so pro on Gerts interface as you can do anything to 2002.

[jamie123]

i know before i went ads i couldnt reset service lights or access any airbag diagnostics. (e36)

[TerraPhantm]

Thanks for the input guys. I've been toying with the idea of buying an e36 sometime down the line as a beater/project car and if it were only minor things that werent accessible, I wouldn't have really cared. Maybe I'll build that DIY ADS interface when I get some time

[WoLF]

If you figure it out, let me know. I'd love to be able to access the GM5 or LCM on my dad's 2001 Z3 (has both ADS and OBD2 interfaces). He just wants the lights to flash when he locks/unlocks the car!
My KKL Vagcom cable won't do the trick from the OBD2 port. Wont work with the ADS port even with a OBD2->ADS converter.

Guess I may need Gert's cable and an old laptop I have laying around with a serial port... Anyone want to loan me Gert's cable for a week? :)

[TerraPhantm]

If you figure it out, let me know. I'd love to be able to access the GM5 or LCM on my dad's 2001 Z3 (has both ADS and OBD2 interfaces). He just wants the lights to flash when he locks/unlocks the car!
My KKL Vagcom cable won't do the trick from the OBD2 port. Wont work with the ADS port even with a OBD2->ADS converter.

Guess I may need Gert's cable and an old laptop I have laying around with a serial port... Anyone want to loan me Gert's cable for a week? :)

That's because those cars need a native ADS interface to access those modules. It's got more to do with the age of the car than what ports the car comes with.

Generally E36s and older need a true ADS interface for full communication, because they use the L-line. For reasons that I don't quite understand, even though the OBDII protocol supports the L-line, the BMW software will only utilize the L-line with an ADS interface. Some modules work fine with just K-line communication, but as discussed in this thread, it's kind of a crap-shoot as to what does and doesn't work.

All modules in E46s and newer cars can be communicated with using a normal OBDII interface. However, the cars that have a 20-pin connector require the 16-20-pin adapter in order to communicate with any module other than the DME and EGS. The point a lot of people get confused on is that even with the adapter, the communication is occuring over the OBDII protocol - it does *not* become an ADS interface. So the adapter is useless for a car that needs the L-line. 2001 and newer BMWs (except the Z3, E38, and possible diesels in Europe) switched over to the 16-pin completely.

E38s and E39s are a bit confusing. Some say they require an ADS interface because the L-line is present, others say that these cars have some redundancy and every module can communicate over the K-line with no issue. I don't know what's true.
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The rest of this is going to be speculation on my part....

The VAG-COM KKL cable which definitely works fine with OBDII cars *does* have an L-line. I know the built in USB to serial converter is an issue, but is there anything else that prevents that interface from being used in ADS mode? If not, then could some clever driver hacking take care of that?

Or heck, the main issue with the ADS driver is that it's pretty much hard coded to look for COM1 and whatever the default hardware address is right? I have to check, but I think VMWare lets you define whatever COM port and hardware address you want for virtual serial ports.

[invictvs]

That's because those cars need a native ADS interface to access those modules. It's got more to do with the age of the car than what ports the car comes with.

Generally E36s and older need a true ADS interface for full communication, because they use the L-line. For reasons that I don't quite understand, even though the OBDII protocol supports the L-line, the BMW software will only utilize the L-line with an ADS interface. Some modules work fine with just K-line communication, but as discussed in this thread, it's kind of a crap-shoot as to what does and doesn't work.

All modules in E46s and newer cars can be communicated with using a normal OBDII interface. However, the cars that have a 20-pin connector require the 16-20-pin adapter in order to communicate with any module other than the DME and EGS. The point a lot of people get confused on is that even with the adapter, the communication is occuring over the OBDII protocol - it does *not* become an ADS interface. So the adapter is useless for a car that needs the L-line. 2001 and newer BMWs (except the Z3, E38, and possible diesels in Europe) switched over to the 16-pin completely.

E38s and E39s are a bit confusing. Some say they require an ADS interface because the L-line is present, others say that these cars have some redundancy and every module can communicate over the K-line with no issue. I don't know what's true.
--------------------------------------------------------------------
The rest of this is going to be speculation on my part....

The VAG-COM KKL cable which definitely works fine with OBDII cars *does* have an L-line. I know the built in USB to serial converter is an issue, but is there anything else that prevents that interface from being used in ADS mode? If not, then could some clever driver hacking take care of that?

Or heck, the main issue with the ADS driver is that it's pretty much hard coded to look for COM1 and whatever the default hardware address is right? I have to check, but I think VMWare lets you define whatever COM port and hardware address you want for virtual serial ports.

Apologies for reviving a dead thread, but I had a question regarding the OBDII to 20 pin (= ADS?) adapter issue. If the car is an older e46 ('99) which has both ports, would the adapter be enough to communicate with the vehicle? Keep in mind that my OBDII to cord is USB.

From what you wrote, I gathered that the e46s do not need the L-line to communicate through that port, so I should be good.

The car needs an EWS to DME realignment to code a new EWS unit to the DME. My OBDII cord, which works on my '04 e46, cannot even recognize the car on any level. I've tried INPA, DIS and Progman, with no luck. I assume the EWS blocks me from even reading the car at all through the OBDII port? Or could there be more?

Thanks in advance for any help!

Edit: Just realized this was the same member that had already given me input on this subject. I really need sleep lol.

[David Mc]

The OBD port on your pre MY2000 E46 only communicates with the DME and maybe EGS, you will need a true ADS interface to communicate with all modules on this car BUT you should be able to access more modules via the round 20 pin BMW diagnostic port.

[invictvs]

The OBD port on your pre MY2000 E46 only communicates with the DME and maybe EGS, you will need a true ADS interface to communicate with all modules on this car BUT you should be able to access more modules via the round 20 pin BMW diagnostic port.

Will I be able to do the EWS-DME realignment using the 20 pin adapter with my (modified) OBDII cable (USB)?

[gpeterson]

Will I be able to do the EWS-DME realignment using the 20 pin adapter with my (modified) OBDII cable (USB)?

Yes. On my 98 M3 I can talk to DME, EWS, SRS via vagcom cable and OBD-20pin adapter. Kombi (cluster) and ABS require a real ADS interface.

[invictvs]

Yes. On my 98 M3 I can talk to DME, EWS, SRS via vagcom cable and OBD-20pin adapter. Kombi (cluster) and ABS require a real ADS interface.

Great! Do you know why my set up was unable to recognize anything from the OBDII port though? Would the EWS block me or something? This car is 40 min away so I want to make sure I have everything set so I don't drive for nothing.

Thanks!

[KevinMullins]

Do you know why my set up was unable to recognize anything from the OBDII port though?

The OBD port is probably missing pin #1, which is the ignition signal. Also make sure your diagnostic cable has pins 7 & 8 jumpered together inside otherwise you will be missing a communication data line. (pin 8 is also usually missing under the dash in the OBD port)
If you get a 20 pin harness adapter make sure it has continuity from pin 16 (round side) to pin 1 (OBD side). Ask the vendor if need be before buying. This is often missing in aftermarket cheap versions.

[invictvs]

The OBD port is probably missing pin #1, which is the ignition signal. Also make sure your diagnostic cable has pins 7 & 8 jumpered together inside otherwise you will be missing a communication data line. (pin 8 is also usually missing under the dash in the OBD port)
If you get a 20 pin harness adapter make sure it has continuity from pin 16 (round side) to pin 1 (OBD side). Ask the vendor if need be before buying. This is often missing in aftermarket cheap versions.

I believe my OBDII cable is modified in that way; it works with my 2004 e46, but I'm not certain about the adapter I purchased. It said it was for BMWs so I really hope it is; I'll have to ask. Thank you!

[betaruce]

agree with the above. i can tell you my case for your reference
my car is 2000 z3 with both 16pin and 20pin
if you want to assess all modules, definitely use the 20pin one
i am using Gert's cable, but I am setting it and ediabas to OBD mode instead of ADS mode (because only work in OBD mode but not ADS mode)
so I am using an ADS interface in OBD mode. Someone suggest that maybe because I don't have a real serial port (I use PCMCIA-serial port card) but I am not sure

[newtoe46]

I found on a site that changing

Hardware: ADS in obd.ini allows use of L-line interface over OBDII for OBDII cars with box connectors but haven't treid it yet

[David Mc]

I doubt that this will be the case, if you look at the BMW Electrical Troubleshooting Manual for the E36, the OBD port has no physical connection to the L line of the data port, so you would also need to run an extra wire from the round 20 pin BMW diagnostic port to your OBD port under the dash.

[newtoe46]

Correct. However connecting straight into the round 20-pin port using a K-Line interface and changing that setting allows for GT1 to automatically detect the car and ignition on in INPA is detected. Still can't access older modules like the GM4/ZKE.

Anyone know where to buy a true ADS dongle nowadays?

[David Mc]

Interfaces4beemers.net, Benemorius, do-it auto.de or One Stop Electronics.

[newtoe46]

Interfaces4beemers.net, Benemorius, do-it auto.de or One Stop Electronics.

Thanks

[DrCharles]

I was considering buying the ADS cable from Benemorius, since my E34 requires it.
But will it also work with my E38 and E39 (K-line)? He didn't answer my question on ebay.

I do have the Chinese PA Soft 1.4 ($29) which is working fine on both the E38 and E39. No soldering or jumping required, just use the 20 pin under the hood.