Results 1 to 13 of 13

Thread: 91 ZR1

  1. #1
    Tuner in Training
    Join Date
    Sep 2002
    Location
    Posts
    19

    91 ZR1

    I am trying to read the pcm from a 1991 ZR1 (LT5).
    I tried to jumper A to B on ALDL and read from M. I used the same cable I used on my L99. I tried to use PCMCOMM, but I am not having any luck. Any idea what I am doing wrong? Is the baud rate wrong?

  2. #2

    Re: 91 ZR1

    I think a 91 is 160 baud.. are you using 8192?
    do you have the number of the ECM? 730, 749 etc?

    this is what I come up with for a 91 LT5

    1228331
    Application: 1990-91 5.7 DOHC V8 SFI “J” LT5
    1991 Vauxhall Lotus Carlton 3.6 Twin Turbo
    MEMCAL IDs: “J”: ANHX, AUAH, ARZR, AXFK, AYBK, BFXB
    Lotus: AXSH, …
    EPROM type: 27C256


    found this for a L05:

    16136965
    Application: 1992-93 4.3 V6 TBI “Z” LB4
    1991-93 5.0 V8 TBI “E” L03 (exc. “F” body)
    1991-93 5.7 V8 TBI “7” L05
    MEMPAK IDs: …
    CALPAK IDs: …
    Program ID: 98 ($62)
    Pgm ID Addr: $D004
    Scan ID Addr: $D002:$D003
    EPROM type: 2732
    EPROM offset: $D000

    the top one is an 8192 i think and the bottom is a 160 they are P4 and C3 respectively
    Business Network Solutions - for all your PC, network, printer and computer security needs.

  3. #3
    Tuner in Training
    Join Date
    Sep 2002
    Location
    Posts
    19

    Re: 91 ZR1

    The PN for the ECM is 1228331 and it is a 5.7 DOHC V8 "J" LT5 with 2 sets of injectors (16 in total),

    should I be able to read this ECM with PCCOMM?

  4. #4

    Re: 91 ZR1

    I'll check.. but I think PCCOMM is for 160 baud
    have you tried any of the other free programs like winaldl or freescan? Just to verify its not a cabling type issue?

    BTW what are you using for a cable?
    Business Network Solutions - for all your PC, network, printer and computer security needs.

  5. #5

    Re: 91 ZR1

    It's 8192 baud:

    ENGINE USAGE: 5.7 SFI - LT5 (VIN = J) 1991
    DATA PIN: READ DATA ON PIN "M" OF ALDL CONNECTOR
    BAUD RATE : 8192 BAUD - BI-DIRECTIONAL

    Mode $01 request: $F4,$57,$00,$01,$B4
    BCM is bus master, so you need to suspend (and/or emulate) normal PCM/BCM message schedules while logging data.

    Don't jumper A and B - only do that if you want the MIL to flash trouble codes to you.

    Regards
    Paul

  6. #6
    Tuner in Training
    Join Date
    Sep 2002
    Location
    Posts
    19

    Re: 91 ZR1

    I'll check.. but I think PCCOMM is for 160 baud
    have you tried any of the other free programs like winaldl or freescan? Just to verify its not a cabling type issue?

    I tried freescan, but it didn't have a list for my vehicle, I am not familiar with winaldl, maybe I'll look for that.


    BTW what are you using for a cable?

    I made a cable following the directions @ http://www.mindspring.com/%7Eamattei/aldlif.jpg, and I have read and flashed my 94 L99 with it.

    Mode $01 request: $F4,$57,$00,$01,$B4
    BCM is bus master, so you need to suspend (and/or emulate) normal PCM/BCM message schedules while logging data.

    Sorry, I am not understanding this, I am pretty "green" when it comes to electronics, or programming. ???

    Don't jumper A and B - only do that if you want the MIL to flash trouble codes to you.

    This I can understand! ;D

    This engine is not running right now, (injectors not firing) it is showing error code 46 (Pass key, aka VATS), I checked for voltage on pin D7 and I have 5 volts, I am not sure of the frequency though (I am not sure how I could check the frequency without a scope). I want to connect to see if the PCM is calling for 0 pulsewidth on injectors.
    I think I am going to pull the chip and have a new one burned that eliminates the VATS.



  7. #7

    Re: 91 ZR1

    frequency is 50hz.. I have a circuit that uses a 555 up in the electronics thread. That can produce that signal no problem.
    Business Network Solutions - for all your PC, network, printer and computer security needs.

  8. #8
    Tuner in Training
    Join Date
    Sep 2002
    Location
    Posts
    19

    Re: 91 ZR1

    Yes, I built that generator, it worked fine on my L99, I tried it on this LT5 , but it doesn't help.

  9. #9
    Tuner in Training
    Join Date
    Sep 2002
    Location
    Posts
    19

    Re: 91 ZR1

    Any one know which free program can read this PCM?
    I have tried
    PCCOMM - (nothing happens)

    Freescan - using GM 410B, they communicate, but the values are all wrong.

    I tried EFI Live V4 eval - but can't find an .xml to work with this PCM, and I am not sure how to modify an existing one to work.


  10. #10

    Re: 91 ZR1

    Kevin,

    I tried sending you some info but your listed email address bounced. Send me an email at [email protected] and I can reply with the info.

    Regards
    Paul

  11. #11
    Tuner in Training
    Join Date
    Sep 2002
    Location
    Posts
    19

    Re: 91 ZR1

    Latest news,

    I had to cut the VATS wire from the CCM to the ECM and then install my VATS module simulator, the engine then fired up.

    With a lot of help from Paul Blackmore I was able to create a definition file for EFIlive 4, thanks Paul.

    One issue that was a problem was that the cable I was using obtains it's power from the laptop. In order for the laptop to supply power to the cable the program needs to turn on the power.
    I beleive that some programs do this in the background, but EFIlive 4 allows you to turn the power on or off on these pins, the default is off.

    The 2 pins are refered to as DTR and RTS.

    I beleive that pin 4 on a DB-9 or pin 20 on a DB-25 is the DTR and pin 7 on a DB-9 or pin 4 on a DB-25 is the RTS. Is this correct?

    I have no idea what DTR or RTS are abbreviations for.
    Anyone?

    To turn these pins on in EFIlive 4 go to Properties on the tool bar or (Crtl+Alt+p) and under Comms, interface cable, check the boxes- Hold DTR line high: and Hold RTS line high: the cable should now be supplied with power.

    I am going to have the MEM CAL reburned to eliminate the vats.

    I am getting a bit flag turned on, "improper shutdown" does anyone know what variables turn this flag on? Or what its purpose is?

    Kevin



  12. #12

    Re: 91 ZR1

    DTR = data terminal ready
    RTS = ready to send
    Business Network Solutions - for all your PC, network, printer and computer security needs.

  13. #13
    Guest
    Guest

    Re: 91 ZR1

    I'm having the same problems communicating with my 92! Could you please send me that definition file for EFIlive 4 or any other info that might help!!!!!
    [email protected]

Similar Threads

  1. corvette zr1
    By rattle in forum OBD-I & OBD-II Hardware And Communications
    Replies: 0
    Last Post: 05-17-2005, 11:33 PM