TunerPro 8192 ODB1 Connectivity

Discussion in 'Tools, Procedures, and Testing trouble shooting' started by bytor, May 13, 2014.

  1. bytor

    bytor Well-Known Member

    I have been getting familiar with the old school ODBI 1227165 ECU on my 87 Corvette. Did some research on what PC based scan software was a good fit and decided to use TunerPro5 with a ALDL to USB cable from these guys. http://www.aldlcable.com/ It took me some time getting the ECU to talk to the PC at the higher speed baud rate (8192). The 1227165 in 87 was a transition unit that could communicate at both 160 and 8192 baud. To start the data streaming, you must place a 10K resistor across A-B of the ALDL connector. My USB cable has a jumper for this that makes it easy. Once this is done, the ECU will start streaming a subset of data at 160 baud. You have to tell it to switch over to 8192 baud. The ECU will transmit at 160 baud stopping briefly to ‘listen’ for commands from the scan tool/PC. If it receives the correct command sequence it will switch over to 8192 baud. It took me a bit of time to figure out how to get TunerPro to send this code. After some research, I have it working. What got me going on the right track was choosing the correct .xdf (ECU bin file definitions) and .adx (data stream definition) files. In my case, I was attempting to use the $32 mask files and they worked fine at 160 baud but not 8192. I found a recommendation to use the $6E mask files. These files had the foundation for sending the commands to the ECU but I still could not get it to work. The missing link was the ‘listen for silence’ command in TunerPro. Once I added this to the mix, it works like a champ. Here's the detail on how to set up the definition file in TunerPro.

    1. Load the 1227165 $6E mask in TunerPro by selecting it in the menu Acquisition > Load definition file menu.

    2. The edit it by selecting menu Acquisition > Edit definition

    3. Under the ADX Header Data expand the ‘Commands’ heading to list the commands/macros.
    This is where the command to start the 8192 baud communications reside.

    4. We need to add the missing ‘listen for silence’ command. This will cause TunerPro to listen to the serial data stream and as soon as the ECU stops
    transmitting temporally, TunerPro will transmit the command to switch over to 8192.
    Here’s a screen shot of how to setup the wait for wait time command.

    5. Here’s the command that causes the ECU to switch over to 8192.

    6. Here’s the command the listens for the response from the ECU

    7. Here we take the three commands listen for silence, send command and listen for response and add them to a macro.
    The macro is executed once the initial serial communications connection is established between the PC and ECU.

    Here’s the overall connect sequence.
    1. Connect the ALDL cable with the 10K resistor in place to the ALDL connector and PC.
    2. Start TunerPro.
    3. Turn the car key on ACC
    4. Click the connect icon in TunerPro. TunerPro will connect, run the macro and start monitoring the ECU stream at 8192 baud.
    5. You can now remove the 10K resistor to put the ECU in normal run mode.
    6. Start the car, start logging and go for a ride...

    I couldn't find a clear cut description of how to set this up and had to piece it together. It was a good learning experience. I hope other beginners find it helpful.

    This generation of GM ECU's are interesting. It's amazing how simple the processor, code and electronics is with these things. GM had a clue to what they were doing. Obviously, the modern ECU's will run rings around the older ones and monitor hundreds of data points instead of 64.

    Interesting links:
    http://home.earthlink.net/~cliff_harris/1227165/index.html Good source for 1227165 schematic and ECU waveform details.
    http://www.ws6transam.org/aldl_35.html ECU serial datastream details.

    Attached Files:

  2. grumpyvette

    grumpyvette Administrator Staff Member

  3. mathd

    mathd solid fixture here in the forum

    TunerPro is the best program for this i think, there is also TTS datamaster, a little easier to use.
    For the 6.5 truck am using GMTD scan tech(work ONLY with the 6.5 diesel), it let me set TDC offset/injector pump timing, stuff that can't be done with the others.

    One alternative to the aldl cable. is the Arduino FT232RL USB to Serial Module USB to TTL level
    Its like 9$ on ebay, thats what am using with my truck. works perfectly.
    You just connect the RXD and TXD together to pin M(for 8192 baud, or E for 160baud) and GND to GND (pin A)

    I don't remember exactly but on the aldl connector, usually there is one port for 160(pin E) and one for 8192 band(pin M) But some transition model like yours can be a pita to get working, nice job there :).
    and there is other value for the 10k that can be used(pin A and B), there is 4 option

    Open - normal mode
    Grounded - Diagnostic mode(will flash the check engine giving you the DTC code)
    10k - aldl mode (set rpm to 1000 and timing to 10° that also turn off some other functions)
    3.9k - Field Service mode/factory test mode(its kind of a backup computer is the ECM fail, so you still can get the car"barely" runing) it will ignore some/most sensor, so if it run better in that mode it probably mean you have a defect sensors.
  4. AWDTwinTurbo

    AWDTwinTurbo New Member

    I know I'm bumping an old thread but I attempted this process and I did not succeed in connecting. I'm not sure if its the ALDL cable that I have or if it's something else going on. I am able to connect using the 1227165_160 ads file and get some data to display (much less to scan in that ads) and of course the update speed is VERY slow. But when attempting the above, TunerPro just says "connecting" and never changes from that. I don't know if I missed a step or not but I have all of the same commands as above in the program and the macro setup the same way but it's almost like it's waiting for silence and it just never happens. How long should it take to connect? Or wait for silence? I will be receiving my Moates unit tonight and maybe that will help me with connecting to this ECU.
  5. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

    can any of you more gifted and knowledgeable computer tuner and diagnostic guys help out here?
    I know I've had similar connectivity issues with other tuner software and diagnostic software,
    but I'm not all that familiar with his particular software.






    Last edited: May 17, 2018
  6. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    I will take a look today Grumpy.
    I have been around TUNER PRO.
    Race Shop.
    The EFI Tuners all used.

    I was the Bare Block To fully assembled Race engine builder.
    Installed in the car too by me.
    Turn key ready to fire.
    EX BOSS & Tuner took over.
    My job task done.
    Last edited by a moderator: May 17, 2018
  7. AWDTwinTurbo

    AWDTwinTurbo New Member

    I have to verify something when I return home... I'm just seeing that Pin M is the bottom right of the ALDL connector on the car... Well I'm dealing with a Beretta that GM modified and put this 1227165 ECU into and I'm starting to think the OBDI connector is lacking that pin. That would explain why I can't connect at the 8192 baud rate.

    I'll report back with my findings. That combined with my new APU1 that is showing up today may resolve my scanning woe's.
  8. AWDTwinTurbo

    AWDTwinTurbo New Member

    So my ALDL socket did not have a pin at location M. That was easily added when I found that it just taps off of pin E. So that's in place and if I try to use the 1227165_6e ADX file to connect, it will connect but I end up getting constant data errors. I'm only able to connect using the 1227165_160 ADX that I got from Tuner Pro's website.
  9. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

    good info too know, please keep us informed if youve found a working solution and the part number and supplier of the cable that works so others may benefit from your research

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