W202 98 petrol obd2 diagnostics

[jwhaslam1990]

Hi all,

You may have had people ask this sort of thing before, I've done alot of trawling through the internet and it seems to come up alot and everyone has a different opinion.

Basically I have a W202 98 C200 that has the 38 pin diagnostic plug. Naturally seeing as I had the obd2 bluetooth jobby for other cars to read Android torque, I thought I would look to see if I could get it to work on the Merc. I purchased a 38 pin male merc plug to 16 pin female obd2 adaptor off of the bay.

Internally the cable contains the following connections...
38 pin end ------- 16 pin end
1 ------- 4+5 signal ground
3 ------- 16 battery power
4 ------- 7 K line

I tried this with no joy , so looked on the internets again which suggested that to read the ISO 9141 protocol I would need to read the L line of the ecu as well so i cobbled a connection between pin 15 of the 38 pin to pin 15 of the obd connector. Alas, this also did not work.

I have only tried to use this with an ELM327 v1.5 bluetooth reader with Android torque on s3 and scantool on laptop with vista but nothing seems to work, I get power to the scanner but can't connect to the ECU . Any one have any advice or an opinion on anything I've done?

Any help would be greatly appreciated many thanks.

James

 

[jwhaslam1990]

bump...

 

[kth286]

but surely your 98 car will not have OBD2. It came in around 2001 for Merc

which was the mandatory time limit by the regulators for introduction.

Some manufacturers introduced it earlier I guess.

 

[jwhaslam1990]

Yes I knew that was the case but I've seen stories across the internet where people have got pre 2001 models able to read with an obd2 reader, reading from the K and L line of the ECU or in some cases just the K line, it would only read the engine information and show what is mostly already displayed on the dash but would still be useful, especially if it could flag up fault codes!

 

[alabbasi]

OBD2 has been available on every car built after 1996 in the US. My 1997 W210 has it.

 

[jwhaslam1990]

Unfortunately the obd socket wasn't mandatory in EU spec cars until 2001, so stuck with the 38 pin. My thinking is that it will be the same wiring as the US spec models apart from an additional harness which connected the correct outputs of the ECU to the obd connection in the cab, so must be able to adapt something from the 38 pin that will read through an obd scanner!

 

[kth286]

what additional info are you expecting via obd2 socket verses the 38 pin plug you already have ?

 

[John Jones Jr]

Sometime back I inquired about an OBD scanner for the '98 W202 (which is not OBD2). The supplier advised on buying a scanner suitable for OBD2 and the connection cable from 32 pin to 16 pin and the scanner would function correctly.

 

[jwhaslam1990]

I just want to make use of the ELM327 bluetooth reader I already have for other cars,
I have already bought the 38 to 16 pin adapter cable, as mentioned in my first post I have had this in pieces and described the connections.
I found a thread last night that mentioned being able to read the data on k line through an obd scanner on kwp2000 protocol but an initiation code had to be communicated to the ecu initially.

 

[shirleydrive]

Have a look at this wiring diagram. Looks like it is for a US E320 which would be OBD2 compliant. You may be able to modify your 38 pin to 16 pin OBD socket .

http://www.autolib.diakom.ru/CAR/Mercedes-Benz/1997/E320/SYSTEM WIRING DIAGRAMS/6223.pdf

Mike

 

[jwhaslam1990]

Thanks for that, it looks as though (according to that schematic) pin 4 of the 38 pin is the one to read K line from as this connects to pin 7 of the obd output, so that clarifies that what I have setup should be right, just doesn't work...

I'm thinking of maybe butchering into the can high and can low signal lines somewhere on the car and reading from there, has anyone tried this before?

 

[hfmscan]

Hi all,

I have only tried to use this with an ELM327 v1.5 bluetooth reader with Android torque on s3 and scantool on laptop with vista but nothing seems to work, I get power to the scanner but can't connect to the ECU . Any one have any advice or an opinion on anything I've done?

Any help would be greatly appreciated many thanks.

James

Hello,
Plese read my internet page www.HFMscan.com