General Specification Electrical Function gmw3110 General Motors Local Area Network Enhanced Diagnostic Test Mode Specification

GM WORLDWIDE ENGINEERING STANDARDS 
GMW3110 
© Copyright 2010 General Motors All Rights Reserved 
February 2010 
Page 116 of 336 
number supported in a single request. Verify proper response, containing data for all of the requested 
$PID(s). 
7. If applicable, repeat the last procedure but include a secure PID in the request. Ensure that this is done at 
a time when security access has not been granted. Verify the proper response for the unsecure PID(s) and 
that no data is reported for the secure PID. 
8. If applicable, use service $27 to access security and then repeat the previous procedure. Verify that the 
proper response is sent including data for all PIDs in the request. 
9. Send a physically addressed $22 message with less than two bytes in the $PID field (0 or 1 data byte after 
the service indentifier $22). Verify the negative response ($7F $22 $12 - SubFunctionNotSupported-
InvalidFormat). 
10. Send a physically addressed $22 message with more data bytes than allowed per the maximum request 
message length (see pseudo code above). Verify the negative response ($7F $22 $12 - 
SubFunctionNotSupported-InvalidFormat). 
11. Send a physically addressed $22 message for multiple $PIDs (if the ECU supports multiple PIDs in a 
single request) where all requested $PIDs are not supported by the ECU. Verify the negative response 
($7F $22 $31 - Request Out Of Range). 
12. If the ECU supports the use of negative response code $78, send a $22 message to the ECU with a valid 
$PID where the ECU needs more than P2
C
ms to read data bytes from memory and send the positive 
response. Verify that the ECU sends the negative response ($78 - RequestCorrectlyReceived-
ResponsePending) within P2
C
ms followed by a positive response (reference application timing section of 
this specification). 
13. (If applicable) Send a request for a valid $PID at a time when ECU internal conditions would not allow the 
data to be retrieved (e.g., EEPROM failure) and verify that the ECU sends the correct negative response 
($7F $22 $22 ConditionsNotCorrect)). 
14. If applicable, send a physically addressed $22 message for one security code (as defined in the Vehicle 
Theft Deterrent SSTS) required $PID (that is supported by the ECU) at a time when the security code has 
not been entered. Verify the negative response ($7F $22 $31 - Request Out Of Range). 
15. If applicable, enter the security code then repeat the request in the previous procedure and verify the 
appropriate positive response and data content. 
16. If applicable, send a physically addressed $22 request message for multiple $PIDs (if the ECU supports 
multiple PIDs in a single request), where at least one, but not all, of the requested $PIDs is supported by 
the ECU and include a security code required PID in the request. Ensure that this is done at a time when 
the security code has not been entered. Verify the proper response for the unsecure PID(s) and that no 
data is reported for the secure PID. 
17. If applicable, enter the security code and then repeat the previous procedure. Verify that the proper 
response is sent including data for all PIDs in the request.