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

SecurityKey (high and low bytes) 
The Key parameter in the request message is the value generated by the security algorithm corresponding to a 
specific seed value. 
8.8.3 Positive Response Message Definition. 
Table 103 indicates the separate message structures for the 
positive responses relating to the requestSeed and sendKey request levels.
 
Table 103: SecurityAccess Positive Response 
Data Byte 
Parameter Name 
Cvt 
Hex Value Mnemonic 
#1 
Security Access Positive Response Service Id 
M 
67 
SIDPR 
#2 
RespLevel = [
requestSeed
sendKey ] 
M 
xx 
xx + 1 
RPLEV_ 
RSD 
SK 
#3 
#4 
SecuritySeed = [
HighByte 
LowByte ] 
M
4
0000 thru 
FFFE 
SS_ 
HB 
LB 
Where: 
M
4 
= Mandatory if request level is requestSeed. Not present if request level is sendKey. 
8.8.3.1 Positive Response Message Data Parameter Definition (Table 104). 
Table 104: Response Message Data Parameter Definition 
Definition 
RespLevel 
This byte is an echo of the sub-parameter from the request message. 
SecuritySeed (high and low bytes) 
The seed parameter is a data value sent by the ECU and is used by the tester when calculating the key 
needed to access security. The SecuritySeed data bytes are only present in the response message if the 
request message was sent with the sub-parameter set to requestSeed. 
8.8.4 Supported Negative Response Codes. 
The following negative response codes shall be implemented 
for this service. The circumstances under which each response code would occur are documented in 
Table 105. 
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