Failure to establish communication with Chev Perf LS376/480 ECU

Rich Kruger

GT40s Supporter
My car starts and seems to run well (Didn't get out of driveway yet). I was unable to establish communication with the ECU. I am suspicious of the Infinity box DLC connector wiring. I verified grounds at pins 4 and 5 as well as Battery power at pin 16. There are two other wire bundles in the connector a set of conjoined tan wires and a set of conjoined tan/black wires. I thought there should be at least one other wire. Can somebody check their pinouts at their DLC and advise me their colors and positions. Thanks in advance
 
What are you trying to connect with?.....have you tried the scan tool on a different vehicle to make sure it's not the scan tool? If the scan tool works but won't connect to the LS ECU, I would contact GMPP thru the paperwork that came with the engine and see what they have to say....this should be a warranty issue.
 

Rich Kruger

GT40s Supporter
Tried two different scanners that I know work. Before I disassemble the Ecu connector I just wanted to check the present configuration. I understand the Ecu communication is through pin 58 on the blue Ecu plug.
 

Dan Carter

Supporter
Rich

As soon as it cool off (index here at 105), I’ll take a picture of my plug in. That may help you with the wires. I extended my harness to reach the cockpit but it’s color coordinated (pretty sure anyway). Probably best Saturday morning.
 

Dan Carter

Supporter
Rich

Attached is a picture of my cockpit ECU port (5 wires). However, I guess when I extended my wires, I did not stay true to GM colors. Saturday I will have some ECU work to do, and I may see the GM vs my continuation junction and can trace them back for you if you still need it. It would be easier for one of the new builders to take a look at their harness and send you a pick. Let me know if I can still help. Sorry.

It cooled off today to 104. I need a jacket.

IMG_2901.JPG
 

Rich Kruger

GT40s Supporter
Thanks Dan. Glad it cooled off:p Just the positions of the pins may help I may swap the LAN wires to see if it works
 
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