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

CT
150
0
req
con
ind
ind
ind
ind
ind
ind
ind
Tester internal status:
RC78PendingEcuCounter
RC78PendingEcuList
P2CTReloadValue
+1=1
ECU#1
5100
-1=0
ECU#1
ECU#3
150
0
150
no change
no change
no change
+1=2
ECU#1
ECU#3
5100
-1=1
ECU#1
ECU#3
no change
no change
no change
no change
no change
no change
no change
--``,,``````,``,,``,,,`,`,`,,-`-`,,`,,`,`,,`---
CameraLoops.com

---

GM WORLDWIDE ENGINEERING STANDARDS 
GMW3110 
© Copyright 2010 General Motors All Rights Reserved 
February 2010 
Page 59 of 336 
Figure 28: Tester P2
CT
* Timing Parameter Definition - Multiple ECUs Responding 
with UUDT Response Messages 
In Figure 28, the tester transmits a functionally addressed service $AA or $A9 request message and three 
ECUs respond. Two ECUs request enhanced response timing and one ECU immediately starts to respond 
with its UUDT message. Based on the general handling of P2
CT
the tester has to restart the P2
CT
timer with 
each starting response message (first UUDT response message) provided the response is associated with the 
request message (e.g., the Data Packet Identifier (DPID) number in the UUDT response message to a service 
$AA request message must match the list of requested DPID numbers embedded in the transmitted request 
message). At the point in time when the tester receives the first negative response with response code $78 the 
tester modifies the reload value of P2