ALDL cable gives random data

Holden/Delco Tuning. ALDL, OBD 1.5. Circa 1989 to 2004.
weezlebub
Posts: 6
Joined: Mon Dec 30, 2019 9:44 pm
cars: VY

ALDL cable gives random data

Post by weezlebub »

I have VY commodore and I built 2 transistor ALDL to serial cable and using 1.05 adx file from this site. when I use tuner pro rt it connects and makes tune on car but all the data showing through the software is all random and its not indicating any data errors. is this common with 2 transistor cable do i need to build max232 cable instead or maybe shorten wires from the ODBD port theyre about 30cm long at the moment. I tried reconnecting a lot of times but it always shows random data
User avatar
j_ds_au
Posts: 384
Joined: Sun Jan 25, 2015 4:21 pm
Location: Sydney

Re: ALDL cable gives random data

Post by j_ds_au »

weezlebub wrote:I have VY commodore and I built 2 transistor ALDL to serial cable and using 1.05 adx file from this site. when I use tuner pro rt it connects and makes tune on car but all the data showing through the software is all random and its not indicating any data errors. is this common with 2 transistor cable do i need to build max232 cable instead or maybe shorten wires from the ODBD port theyre about 30cm long at the moment. I tried reconnecting a lot of times but it always shows random data
I presume you have a V6, otherwise the VY PCM/ECU doesn't talk ALDL. You might try using the OSE Flash tool here to read the cal and check if you get consistent cal data back, that will validate your ALDL interface.

Joe.
User avatar
antus
Site Admin
Posts: 8237
Joined: Sat Feb 28, 2009 8:34 pm
cars: TX Gemini 2L Twincam
TX Gemini SR20 18psi
Datsun 1200 Ute
Subaru Blitzen '06 EZ30 4th gen, 3.0R Spec B
Contact:

Re: ALDL cable gives random data

Post by antus »

Yep your not the first person to have trouble with the 2 transistor circuit. Im not sure if it works at all. :( there are some other threads about it but with no successful resolution.
Have you read the FAQ? For lots of information and links to significant threads see here: http://pcmhacking.net/forums/viewtopic.php?f=7&t=1396
weezlebub
Posts: 6
Joined: Mon Dec 30, 2019 9:44 pm
cars: VY

Re: ALDL cable gives random data

Post by weezlebub »

thanks didn't have any luck with flash tool it was just waiting for heartbeat and wouldn't connect. Have a max232 so will try build a cable with that instead.
User avatar
delcowizzid
Posts: 5493
Joined: Sat Feb 28, 2009 8:38 pm
Location: Wellington NZ
Contact:

Re: ALDL cable gives random data

Post by delcowizzid »

Vx vy is tricky they need very good timing and filtering in the cable to get a connection due to the limited time between packets from all the modules. Best off just buying the aldl cable off here. I've tested even the cheap ttl to USB boards and they are to slow on vx
If Its Got Gas Or Ass Count Me In.if it cant be fixed with a hammer you have an electrical problem
User avatar
j_ds_au
Posts: 384
Joined: Sun Jan 25, 2015 4:21 pm
Location: Sydney

Re: ALDL cable gives random data

Post by j_ds_au »

delcowizzid wrote:Vx vy is tricky they need very good timing and filtering in the cable to get a connection due to the limited time between packets from all the modules. Best off just buying the aldl cable off here. I've tested even the cheap ttl to USB boards and they are to slow on vx
Yeah, timing is tricky via USB. Sometimes tweaking the USB latency setting helps. Other USB drivers installed like com0com can also cause problems.

OTOH, if wb is using a real serial port, timing tends to work out better.

Joe.
weezlebub
Posts: 6
Joined: Mon Dec 30, 2019 9:44 pm
cars: VY

Re: ALDL cable gives random data

Post by weezlebub »

Unfortunately i am still having the same issue after building max232 cable. :hmm:
I use the schematic http://www.techedge.com.au/vehicle/aldl8192/8192hw.htm.
I left out resistors r2 and r3 cause my vy series 1 v6 doesn't have those pins on the car. Is that right?
Wondering if i got wrong setting somewhere
User avatar
antus
Site Admin
Posts: 8237
Joined: Sat Feb 28, 2009 8:34 pm
cars: TX Gemini 2L Twincam
TX Gemini SR20 18psi
Datsun 1200 Ute
Subaru Blitzen '06 EZ30 4th gen, 3.0R Spec B
Contact:

Re: ALDL cable gives random data

Post by antus »

The diode on pin 12 used to be backwards on that diagram and i think still is. Try flipping it around. What usb interface are you using? Many cant do 8192 baud.
Have you read the FAQ? For lots of information and links to significant threads see here: http://pcmhacking.net/forums/viewtopic.php?f=7&t=1396
weezlebub
Posts: 6
Joined: Mon Dec 30, 2019 9:44 pm
cars: VY

Re: ALDL cable gives random data

Post by weezlebub »

Ok I will try diode flip. I'm using a serial port on the dock of my dell laptop. It has 9600bps as default speed in device manager but i assume it is able to use 8192bps if software requests it?
User avatar
antus
Site Admin
Posts: 8237
Joined: Sat Feb 28, 2009 8:34 pm
cars: TX Gemini 2L Twincam
TX Gemini SR20 18psi
Datsun 1200 Ute
Subaru Blitzen '06 EZ30 4th gen, 3.0R Spec B
Contact:

Re: ALDL cable gives random data

Post by antus »

If its old enough that its a genuine 16550 chip behind it then it will. If its a built in usb to serial then itll be no different to needing a compatible usb adapter.
Have you read the FAQ? For lots of information and links to significant threads see here: http://pcmhacking.net/forums/viewtopic.php?f=7&t=1396
Post Reply