Bringing TBI and Multi Port Fuel Injection to a New Level.     EFI Conversions and Tuning! Seattle to Portland! E-mail Tuning Consultant!
Results 1 to 5 of 5

Thread: Bench Flashing OBD II LT1??

  1. #1
    Super Moderator dave w's Avatar
    Join Date
    Feb 2011
    Posts
    3,711

    Bench Flashing OBD II LT1??

    I'm wondering if anyone has a write up / pin out for building an OBD II LT1 Bench Flash tool? I'm curious because the OBD II schematics (attached below) shows two Serial Data pins (C4) Blue 7 and (C4) Blue 30. I've noticed (C4) Blue 20 is an Output / Field Service Enable is connected to the ALDL Connector. I'm not sure if (C4) Blue 20 is needed for bench flashing an OBD II LT1 PCM? I'm not sure if (C4) Blue 20 and (C4) Blue 30 are needed for bench flashing an OBD II LT1 PCM?

    If the OBD II schematics (attached below) are correct, then Bench Flashing the LT1 OBD II PCM needs the following pins connected to the PCM?

    (C2) Black Pin 15 Battery
    (C2) Black Pin 30 Switched Ignition
    (C2) Black Pin 31 Battery

    (C4) Blue Pin 01 Ground
    (C4) Blue Pin 03 Switched Ignition
    (C4) Blue Pin 07 Serial Data

    The links below are to the bench flashing tool offered by EFI Connections:
    http://www.eficonnection.com/eficonn...spx?ItemId=716

    http://www.eficonnection.com/eficonn..._extension.jpg

    I'd like to build my own, and save a few $$!



    dave w
    Attached Images Attached Images
    Last edited by dave w; 01-12-2014 at 09:41 AM.

  2. #2
    EFI GearHead ! EagleMark's Avatar
    Join Date
    Feb 2011
    Location
    North Idaho
    Age
    58
    Posts
    10,477
    These are from TC and someone that came over when Monodax died had donated them. Thanks to (I forget who?)!
    Attached Files Attached Files
    Last edited by dave w; 01-12-2014 at 12:33 PM.

    1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
    1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
    -= =-

  3. #3
    Super Moderator dave w's Avatar
    Join Date
    Feb 2011
    Posts
    3,711
    Quote Originally Posted by EagleMark View Post
    These are from TC and someone that came over when Monodax died had donated them. Thanks to (I forget who?)!
    Thanks Mark!

    The only difference I see with my pin out posted above vs. the .pdf pin out is (C2) Back pin 6, which in the schematic I posted is a reference ground for the TPS and transmission temperature sensor. I don't see any concerns adding ground to (C2) Black pin 6.

    dave w

  4. #4
    Fuel Injected!
    Join Date
    Apr 2013
    Posts
    123
    Quote Originally Posted by dave w View Post
    ... shows two Serial Data pins (C4) Blue 7 and (C4) Blue 30 ... I'm not sure if ... (C4) Blue 30 are needed for bench flashing an OBD II LT1 PCM? ...
    I believe the following is true ... however, I work with LSx engines only ... I don't touch the LT1 ...

    C4 pin 7 is Serial Data to the DLC. C4 pin 30 (and probably pin 29) are UART coms - these are typically coms with a TAC module or a traction control system

  5. #5
    EFI GearHead ! EagleMark's Avatar
    Join Date
    Feb 2011
    Location
    North Idaho
    Age
    58
    Posts
    10,477
    My bench flash wiring for OBDI LT1 is to serial. I was told this is wrong by a well known tuner who had published info as to it going to the other pin, but it has been working for years that way. When I looked at wiring diagrams it was corrrect and the other wires (UART?) were wired to other modules first then PCM.

    1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
    1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
    -= =-

Similar Threads

  1. Tech2 flashing
    By roughneck427 in forum Other EFI systems and related topics
    Replies: 7
    Last Post: 05-13-2016, 03:38 PM
  2. test bench
    By ericjon262 in forum OBDII Tuning
    Replies: 16
    Last Post: 02-01-2014, 06:06 PM
  3. Flashing pcm with stock bin
    By Nu 2ner in forum TunerPro Tuning Talk
    Replies: 19
    Last Post: 06-17-2013, 08:10 PM
  4. flashing 94-95 lt1 .bin file on a 96-97 lt1 computer?
    By jrgcjnl in forum TunerPro Tuning Talk
    Replies: 14
    Last Post: 07-08-2012, 12:12 AM
  5. LC-1 on the bench
    By EagleMark in forum Other EFI systems and related topics
    Replies: 7
    Last Post: 08-09-2011, 11:17 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •