Page 1 of 2 12 LastLast
Results 1 to 15 of 26

Thread: 1995 3.4L Camaro No ECU Response

  1. #1
    Fuel Injected!
    Join Date
    Aug 2019
    Age
    32
    Posts
    21

    1995 3.4L Camaro No ECU Response

    Hey guys, I wasn't really sure where to post this but here goes.

    I'm struggling to get my ALDL cable to receive any information from the car. I've tried connecting with Scan9495 (v6 edition), ALDLDroid (USB), TunerPro. I've also tried Steveo's flash-hack tool as well as ALDL Fast Test and no matter what I do I can't get it to connect. The wiring seems to be good. I have 0 resistance on the grounds, power port has 12v and I have continuity from the wire at the pcm to the pin on the OBD port. I'm seriously at a loss here. Been battling this since early August and figured it was my Red Devil River cable. Ordered a new one that took a month to arrive and still nothing. I was able to read it once with the old cable before it stopped working. The car will start and Idle fine, but driving it is a no-go since it needs to be tuned.

    Anyone have any ideas or suggestions I can try? I've read somewhere that the drivers can cause issues when using laptop programming, but the creator of ALDLDroid told me using it with the app shouldn't have those same issues and the fact that I'm having the same type of connection error across all programs makes me think it's not driver related. Also of note, while using Scan9495 it tells me in the communication tab that I'm missing an engine signal and and actuator signal, but can't seem to figure out why that's happening.

    Any help is appreciated guys

    Thanks,
    Johnny

  2. #2
    LT1 specialist steveo's Avatar
    Join Date
    Aug 2013
    Posts
    4,007
    just a few sanity checks i forgot before, it's a 95 so it's a 16 pin aldl connector, right?

    what pin are you testing for continuity to the ECM data pin? bottom left?

    what part number is the ECM?

    do you only have one COM port on your laptop with the cable connected?

    if you run flashhack, in the 'select interface' screen, what's displayed in the info pane (vendor serial# etc)

  3. #3
    Fuel Injected!
    Join Date
    Aug 2019
    Age
    32
    Posts
    21
    Yeah its a 16 pin. I'm testing continuity at pin 9 (bottom left),

    Im not sure which is the part number on the pcm, but service no. Is listed as 16196742 BPCN
    *86BPCNK350540207* is on the bottom of the tag

  4. #4
    Fuel Injected!
    Join Date
    Aug 2019
    Age
    32
    Posts
    21
    Quote Originally Posted by steveo View Post
    just a few sanity checks i forgot before, it's a 95 so it's a 16 pin aldl connector, right?

    what pin are you testing for continuity to the ECM data pin? bottom left?

    what part number is the ECM?

    do you only have one COM port on your laptop with the cable connected?

    if you run flashhack, in the 'select interface' screen, what's displayed in the info pane (vendor serial# etc)
    Just ran the flash hack with it plugged in. Says
    SER : #AK08HBBZA
    VENDOR: 403
    PRODUCT: 6001

  5. #5
    LT1 specialist steveo's Avatar
    Join Date
    Aug 2013
    Posts
    4,007
    can't see why it wouldn't work, cable is a normal ftdi thing, ecm seems to be the right part#. i wonder if something is wrong with the ECM?

    run something to monitor the bus, is there any data on the bus at all, key on engine off? you can use a terminal program. my eehack tool, in the 'raw command' section does have an idle traffic monitor that's designed for that too

  6. #6
    Fuel Injected!
    Join Date
    Aug 2019
    Age
    32
    Posts
    21
    Not having much luck figuring that out. Just keeps saying "bus is silent"

  7. #7
    LT1 specialist steveo's Avatar
    Join Date
    Aug 2013
    Posts
    4,007
    well something should be talking on that aldl bus......i can only really jump to the conclusion that if the cable is working you don't actually have data/ground to the aldl port where it's supposed to be

  8. #8
    Fuel Injected!
    Join Date
    Aug 2019
    Age
    32
    Posts
    21
    Decided to pull the pins on the obd port to check them. Serial Data pin had ALOT of corrosion. Decided to use the other UART pin from the ls1 in it's place. Still having the same issue, so I pulled the power pin as well. Seems to be dark with a minor green crust on the pin intself. Wondering if I can just forget the OBD port for now and hook up some female wiring ends and hook those up to the appropriate pins on the ALDL cable.

  9. #9
    Fuel Injected!
    Join Date
    Aug 2019
    Age
    32
    Posts
    21
    Swing and Miss. Rewired it all without using the obd port and connected female ends onto the ALDL cable. Have 12v, good grounds and continuity from the ALDL pin to the pcm and no dice. Can't get the ECU to connect at all

    If I wanted to try another ECU, would I just find one with the matching part number, plug it in and check it? If it works I can copy the base p66 table from mine onto it and I'd be good right?

  10. #10
    LT1 specialist steveo's Avatar
    Join Date
    Aug 2013
    Posts
    4,007
    Have 12v, good grounds and continuity from the ALDL pin to the pcm and no dice.
    you generally only need data and ground for a usb ftdi based aldl cable, you can stop worrying about that power wire

    where are you grounding the aldl cable to in this test? most cables ive seen use pin 5, but it's possible some use pin 4 (or both)

    If it works I can copy the base p66 table from mine onto it and I'd be good right?
    not sure what a base table is but you should be able to load whatever compatible bin you want onto another P66 ecm

  11. #11
    Fuel Injected!
    Join Date
    Aug 2019
    Age
    32
    Posts
    21
    I'm grounding both wires to the same chassis ground. I've tried it on a ground in the drivers side footwell area as well as a chassis ground in the engine bay. I'm still new to this so the terminology might be a bit off but I just meant the basic info from the P66 Bin files onto the new pcm. I'm really lost here, I don't see how it can be the PCM when the car will start and idle
    Last edited by Robindehood; 09-14-2020 at 09:11 PM.

  12. #12
    Fuel Injected!
    Join Date
    Aug 2019
    Age
    32
    Posts
    21
    Going to give this a bump as it's still an ongoing issue. I ordered a replacement PCM to test in case mine was shot and I'm still having no dice reading it. I purchased a new RedDevilRiver cable and I'm just stuck. I've updated the drivers and gone through that process at least a dozen times and factory reset the laptop twice in between to ensure that I'm doing the correctly. I'm just stuck guys. What the hell could be going on? I've even tried using the cable with ALDLDroid on my phone and still can't get any info. But, the car will start and run, just not well due to the bad tune on it for the current injectors.

  13. #13
    Fuel Injected!
    Join Date
    Mar 2013
    Posts
    1,470
    I can suggest you build a bench setup to test pcm. Than you can open the case and look for water corrosion.

    Just test on bench first, to remove all incar variables.

  14. #14
    Fuel Injected!
    Join Date
    Aug 2019
    Age
    32
    Posts
    21
    I've opened it up, no visible corrosion or burns or anything in either pcm

  15. #15
    Fuel Injected!
    Join Date
    Jul 2019
    Location
    Orange, CA
    Posts
    757
    I know you don't want to spend any money probably...but how about a known-good cable? The cable I use is this one: http://aldlcable.com/products/aldlobd2u.asp

    It has worked on two different computers, one Windows XP, one Windows 7, with zero issue on either machine.

    If you have a totally different PCM now and get the same exact result...that suggests the problem isn't the PCM at all, but is either between the PCM and ALDL connector, or between the ALDL connector and the software.
    1990 Corvette (Manual)
    1994 Corvette (Automatic)
    1995 Corvette (Manual)

Similar Threads

  1. 1995 camaro owner
    By mullettcar in forum Introductions
    Replies: 22
    Last Post: 06-04-2020, 08:16 AM
  2. no response from pcm is what winflash says, someone give me a hand?
    By Osiel Luna in forum Other EFI systems and related topics
    Replies: 10
    Last Post: 05-16-2020, 03:55 AM
  3. Tunning For Better Throttle Response
    By eutu1960 in forum GM EFI Systems
    Replies: 18
    Last Post: 10-08-2017, 04:04 PM
  4. 1995 TPI
    By jaros44sr in forum Introductions
    Replies: 12
    Last Post: 01-16-2014, 04:46 AM
  5. 95 LT1 throttle response
    By Dewayne_S in forum GM EFI Systems
    Replies: 7
    Last Post: 02-02-2013, 02:56 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
  •