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vsboost
November 21st, 2009, 03:47 PM
Was wondering if anybody has been able to read DTC's from the SRS / ABS system, i think the module is $F7 and $F9 this is for a VT V6 commodore. I have seen in the service manual lots of DTC's up to 130 relating to ABS / SRS faults, also would clearing SRS faults be simply a matter of going into the vehicle data stream editor and under ECM/PCM $0A change the value from $F5 to $F7.

Cheers

Blacky
November 21st, 2009, 08:47 PM
If you used the correct module ID for the SRS and/or ABS modules then, yes you should be able to send the clear DTCs command the same as you would for the ECM.

I don't have any SRS/ABS module info to read/decode their DTCs though.

Regards
Paul

vsboost
November 21st, 2009, 09:03 PM
Thanks for your reply, yea tried using F7 and no go

Blacky
November 21st, 2009, 10:14 PM
SRS module IDs should be in the range $A0..$A7
ABS module IDs should be in the range $90..$97

Scan the chatter and see which module ID's show up.

I'm not sure if you can communicate with modules using those ID's, I've never tried it.

Regards
Paul

vsboost
November 21st, 2009, 10:22 PM
Thanks Blacky, ill give it a go, i was just going by what i seen in the efilive doc under the modules section which says F7 is SRS and F9 is ABS...

Ill let you know :)

PS. when you say scan the chatter, what exactly should i be looking for (never used the chatter)

Blacky
November 21st, 2009, 10:35 PM
It may be you need to use $Fx to send specific commands to modules - I don't know.

The chatter is the BCM or ECM sending a "request" (even ID's) and getting a "response" (odd ID's) from the various modules.

i.e. chatter may look like:

$A0,$57,$01,$02,$XX (BCM or ECM requesting info from module $A0)
$A1,$59,$AA,$BB,$CC,$DD,$XX (Reply from module $A0)
$90,$57,$01,$02,$XX (BCM or ECM requesting info from module $90)
$91,$59,$AA,$BB,$CC,$DD,$XX (Reply from module $90)

Regards
Paul

vsboost
November 21st, 2009, 10:39 PM
I have tried

F2, 56, 0A (this resets the instrument cluster)
just a question to reset the DTC's from the PCM the string is

F5, 57, 0A

Can you tell me what the second (56, 57) byte does

Cheers

Blacky
November 21st, 2009, 10:43 PM
The second byte is the number of data bytes to follow, less $55.

So $55 means no data bytes to follow, just the checksum byte,
$56 means one data byte plus the checksum
$57 means two data bytes plus the checksum
etc

Regards
Paul

vsboost
November 22nd, 2009, 12:34 AM
Just an update

sending $F1,$57,$0A,$00,$AE seems to reset the BCM
sending $F2,$57,$0A,$00,$AD resets the instrument cluster
sending $F9,$57,$0A,$00,$A6 resets the ABS

but

sending $F7,$57,$0A,$00,$A8 does not reset the SRS

this could be because there is still a fault with one of the modules attached to the SDM (just a theory anyway)

Blacky
November 22nd, 2009, 07:42 AM
Try leaving off the second data byte $00 and just send: $F7,$56,$0A,$XX (where $XX is the checksum).

Regards
Paul

vsboost
November 22nd, 2009, 10:31 AM
Try leaving off the second data byte $00 and just send: $F7,$56,$0A,$XX (where $XX is the checksum).

Regards
Paul


Is that possible in efilive, when i modify the datastream definition for CLRDTC all i can enter is the module id eg, F9 and it looks like it makes its own string $F9,$57,$0A,$00,$A6 is there a way i can enter my own..

Also i was looking at some documents i had and it makes references to the SDM (SRS) being on $FA

MODE 10 (CLEAR MALFUNCTION CODES - TESTER TO SDM)
ALDL REQUEST:
- MESSAGE ID = $FA
- MESSAGE LENGTH = $56
- MODE NUMBER = $0A
- CHECKSUM

So i might try on that address.


Thanks for your help :)