Hi guys, I am ordering some EEproms, adapters/sockets, and a programmer from moates.net tomorrow. I am also going to purchase TunerPro RT to use as both my bin editor and ALDL program. I would like to make my own cable to use for ALDL. I have found two different ALDL cable schematics -- moates.net has both listed.

I'm assuming that I'm using the top (ALDL to serial) schematic, which is originally from WinALDL's website. Will this cable work fine with TunerPro RT? I know WinALDL only runs at 160 baud, so I just wanted to verify if the cable WinALDL has spec'd out will run at the higher bitrate transfer that TunerPro RT will support. Also, will I need the 3k resistor between pins A and B to datalog with my 1987 PCM (165)? If so, this means I won't have knock counts output to the ALDL, right? Hopefully I don't need this resistor.

 

I have tested and using theese schematics.

/N.

 

and next one...

 

I've used the two trans style for several cables, and have used it with TunerPro and other scanning software. Bob

 

I used the single transistor circuit with a '747 ecu (C3 type, 160 baud ALDL) but it did not work on a '749 (P4 type, 8192 baud ALDL). I'm using the 2-transistor version now with a 749 ECU. I've used the 2-transisor cable with TunerPro, Freescan, and TTS DataMaster scanning sofware. Brent

 

Which 2 transistor model are you guys using? There are two diagrams listed here that use 2 transistors -- one labeled "Simple ALDL - lotus esprit" and the other one below it. I picked up all the parts I need from Radio shack and am ready to put a cable together for the princely sum of $8

 

I used the "Simple ALDL-lotus esprit" as it is powered from a separate +12vdc source. The other 2-transistor circuit pulls its +12vdc from the RS232 port and some laptops can't drive this circuit (my Omnibook 6000 can't).

I chose to hardwire my aldl cable into the vehicle. Then I just connect the laptop to it with a 9-pin male to female straight thru cable.

Brent

 

Brent, thanks. I'm working with a 165 ECU. Should the same model you used for the ALDL cable work with the 8192 baud 165?

 

AFAIK, it should work just fine.

Brent

 

Thanks again for the quick response Brent. Did you have to use a 3k resistor jumped across A and B on your diagnostic port in order to get the ecu into "ALDL mode", where it will have a high idle and no knock retard, or did you have no problems receiving data without the 3k resistor?

 

It's not needed on either the 747 or 749. Not too sure about the 165 but it might need a 10k across A&B, maybe just to connect. There's a discussion about it here https://www.thirdgen.org/techbb2/sho...l+165+resistor

You might need to search for more info on this as I really have no experience with a 165 ecu.

Brent

 

Brent, did you tie all of the grounds in the circuit to the same ground that comes off the diagnostic port, or did you actually send these to a common chassis ground?

 

Update, I used the Lotus Esprit 2 transistor diagram to make my ALDL. Total cost was around $8. The cable works -- I haven't been able to test it at higher baud because of my 32b mask, but at 160 baud it works properly. Thanks everyone for putting up with my stupid questions!

 

Congrats! This diy stuff is fun, eh?

I guess you got the grounds figured out. Now all the real fun begins!

Brent

 

This diy-efi stuff is quickly becoming absolutely addictive. You should have seen the **** eating grin on my face when I got the ALDL working and my camaro was sitting their with its cammy idle, with a computer displaying data from all the sensors on my 1969 engine. I don't know that I can ever let a carb be "close enough" again!

 

you never specified wether the grounds go to the chassis or not in the circuit.

 

Grounds are grounds. Chassis grounds, electrical system grounds, all are grounds. In this case it is most convenient to tie the grounds in the diagram into the ALDL port ground.

 

Ive built and tested the Lotus Espirit one on a 165, 7730 and a tbi S-10 and seems to work great.

 

very cool. thanx for being specific as i have tried many times to get multiple different circuits to work and haven't had any luck. i found out after making them all that you need to turn off the infrared port ont he laptop and have just started making them againt o try and the first one i am doing is the lotus espirt one so i hope it works. i am using the aldl ground and will test tomorrow haven't finished the circuit yet cuz i dont have a diode. so i will let you guys know.