Results 1 to 9 of 9

Thread: VZ E38 Reverse lockout

  1. #1
    Junior Member
    Join Date
    Sep 2016
    Posts
    13

    Default VZ E38 Reverse lockout

    Hi,

    I have a VZ Commodore set up in a AC Cobra and cannot get the reverse lockout to work.

    Have logged the reverse lockout and it is changing status in the ECU, but the ECU output on the pin is a constant 0.5V. (Log attached)E38_0022.efi

    It should ground out over 5km/h. That part of the harness is stock VZ commodore and is output is on the X2 connector, pin 11.

    Tuner reckons is should be working, however, every other problem we have had has been on his end, and not a wiring issue so I have low confidence.

    Any ideas - is there an alternate pin on the E38 that might be outputting the reverse lockout signal.

    Thanks.

  2. #2
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    28,403

    Default

    Are there any other enables besides vehicle speed...?

  3. #3
    Junior Member
    Join Date
    Sep 2016
    Posts
    13

    Default

    I do not have a clutch position switch but have hooked up a temporary 12v to what would be the right pin if I did, but it did not make any difference. Not sure what parameters can be changed in Efilive as I dont have access to the tune. About to give up on this one and just hook up the reverse lockout to the brake pedal as I know a few others have done. Just figured that would result in greater wear on the reverse solenoid then I would have otherwise.

  4. #4
    Lifetime Member GMPX's Avatar
    Join Date
    Apr 2003
    Posts
    13,148

    Default

    X2 connector, pin 11 is the correct output. One side of the solenoid goes to 12V, the other side to the ECM pin, the ECM will switch it to 0V when on, the ECM pin will sit at 12V when off.
    To test the wiring side the tuner can open up the scantool in V7 and manually control the Reverse lockout solenoid, but just check the wiring on the non ECM side of the solenoid is not going to GND, it needs to be like this.

    Correct:
    ECM X2,11 -----> Solenoid -----> +12V

    Wrong:

    ECM X2,11 -----> Solenoid -----> GND

    Cheers,
    Ross
    I no longer monitor the forum, please either post your question or create a support ticket.

  5. #5
    Junior Member
    Join Date
    Sep 2016
    Posts
    13

    Default

    Thanks Ross, it is absolutely wired right and have double checked it many times. I did start with a stock VZ harness and the x2 connector and associated wiring was pretty much unchanged. I actually currently have the ecu side of the solenoid wired to a little switch on the consul with ground on the other side in order to switch it manually at present. Really has me stumped but at least there is an alternative, just not ideal.

    Cheers

  6. #6
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    28,403

    Default

    Check that you have all the ECM grounds connected.

  7. #7
    Junior Member
    Join Date
    Sep 2016
    Posts
    13

    Default

    I thought that could be it but I can only see one ground in my diagrams X1-73 which is hooked up fine. Are there any others i have missed?

  8. #8
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    28,403

    Default

    I thought there were more grounds than that... I'll see if I can find some factory wiring diagrams.

  9. #9
    Lifetime Member GMPX's Avatar
    Join Date
    Apr 2003
    Posts
    13,148

    Default

    Quote Originally Posted by Shelby View Post
    I thought that could be it but I can only see one ground in my diagrams X1-73 which is hooked up fine. Are there any others i have missed?
    That is the main ground point and as far as I know the other ground pins on the ECM are all tied together anyway.

    However you said "but the ECU output on the pin is a constant 0.5V", with the Reverse Solenoid off that should be at 12V, not 0V. It would be at 0V if the solenoid was grounded on the non ECM side and not connected to 12V.
    As I also suggested, get the tuner to test the solenoid output using the DVT controls in the scantool.
    I no longer monitor the forum, please either post your question or create a support ticket.

Similar Threads

  1. surging in reverse
    By steve40 in forum Gen III V8 Specific
    Replies: 6
    Last Post: May 31st, 2017, 01:52 PM
  2. Stalling in reverse
    By dsltnr in forum Cummins 6.7L
    Replies: 9
    Last Post: May 19th, 2013, 06:43 AM
  3. Tune purchasing lockout
    By saintb6969 in forum Cummins 5.9L
    Replies: 17
    Last Post: March 19th, 2013, 01:18 AM
  4. Reverse lockout T56
    By JuhaniLS1 in forum Gen IV V8 Specific
    Replies: 6
    Last Post: December 6th, 2011, 01:42 PM
  5. Weird issue with Drive to Reverse and Reverse to Drive...
    By 01Blackerado in forum Gen III V8 Specific
    Replies: 5
    Last Post: March 24th, 2011, 08:39 AM

Posting Permissions

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