How do I make an ALDL cable for my Laptop?

kopbet89c4 · 08-02-2005, 01:49 AM

Just out of curiousity, I'd really like to start monitoring everthing that goes under the hood, from BLMS to knock counts. I'm trying to broaden my knowledge of learning the basic steps of TPI tuning. I just got a new (old) laptop, Pentium III with a 9 pin serial port on the back. I just downloaded TunerPro RT. I hear this is one of the programs needed. Is there a way to connect to the ALDL using that 9 pin serial port? So, what is needed and which ones of the 9 pins do I connect to the ALDL terminal of my 89? I see 5 pins on the top and 4 on the bottom in this arrangement(facing the back of the computer):
1 3 5 7 9
2 4 6 8

If anyone knows how to do this, please guide me in making this work. Thanks!

Alvin · 08-02-2005, 02:09 AM

I can't help you with building one as I've always jsut bought one but you can try aldlcable.com if your looking for a cheap cable. They are around $30 US

Morley · 08-02-2005, 03:56 AM

Go here http://www.moates.net/index2.html and click on the software link on the left. Now find and click on " 2 transistor" on the RH side. That is the schematic for the cable you need to build. It costs about $4 in parts and takes a couple hours to assemble.

kopbet89c4 · 08-03-2005, 04:26 PM

I just got my cable from aldlcable.com a few minutes ago. The cable came with a little resistor with the colors stripes gold, orange, black brown. I'm guessing this resistor has something to do with connecting it to the ECU. I just got my laptop and plugged the 9 pin in my laptop, the ALDL to the ALDL connector, and the 12 V power supply. Ran the Tuner Pro RT program and I was lost from there. I clicked on the Tools tab, then ALDL/Datalogging, then connect and it tried to connect and afterwards it said connection failed. How hard is it to connect a laptop and read the ALDL ECU values in realtime?

Morley · 08-04-2005, 05:22 AM

Quote:

Originally Posted by k0rv3tt389

I just got my cable from aldlcable.com a few minutes ago. The cable came with a little resistor with the colors stripes gold, orange, black brown. I'm guessing this resistor has something to do with connecting it to the ECU.

That resistor goes between pins A & B on the car's ALDL for a MAF equipped engine (1985-1989). It is needed to put the ECM into ALDL mode. If you have a speed density system you don't need the resistor.

BTW, the resistor value is 10k ohms.

GordoC4 · 08-05-2005, 04:15 PM

not sure if you can select com1 and com2 in your software but make sure they are enabled in the laptops bio's, sometimes a user will disable them.