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 135 of 336 
Procedure 1: 
1. Send a valid security access request message $03 within 10 s of power-up to an ECU when the 
vulnerability_flag !=$FF (if supported) and the MEC = $00. Verify $7F $27 $37 response. 
2. Repeat step 1 of this procedure periodically (approximately every 500 ms) and verify that the $7F $27 $37 
response is sent each time until the ECU has been powered for 10 s. 
3. Send a valid security access request message $03 within 10 s of power-up to an ECU when the MEC > 
$00 and vulnerability flag not equal to $FF (if supported). Verify the proper positive response message $67 
$03 $00 $00. 
4. Send a valid security access request message $03 within 10 s of power-up to an ECU when the MEC 
equals $00 and vulnerability flag is set to $FF (if supported). Verify the proper positive response message 
$67 $03 $00 $00. 
Procedure 2: 
This procedure is to be performed twice, once while the ECU has the service device control 
restrictions active and once while the ECU has the assembly plant device control restrictions active. 
1. Send a security access request message $03 with an incorrect number of data bytes and verify $7F $27 
$12 response. 
2. Send a security access request message $04 without sending a security access request message $03 and 
verify $7F $27 $22. 
3. Send a valid security access request message $03 and verify the security access positive response 
message $03. Then send a request message $04 with an incorrect number of data bytes and verify the 
$7F $27 $12 response. 
Procedure 3: 
This procedure is to be performed while the ECU has the assembly plant device control 
restrictions active. 
1. Send a valid security access request message $03 while the device has assembly plant restrictions active 
and verify $67 $03 $00 $00 response. 
2. Repeat step 1 of this procedure and then send a security access request message with level $04. Verify 
$7F $27 $22 response. 
3. After performing steps 1 and 2 of this procedure, verify that the ECU keeps the assembly plant device 
control restrictions active. This can be done by sending a device control command that is valid for the 
assembly plant restrictions but invalid for service restrictions and verifying a positive response message.