[General] [VR/VS/VT/VX/VY/VZ] Everything to know about ALDL Diagnostic Cables

[TazzI]

Most of the cables main chip is low voltage, should have a 5v reg in the circuit somewhere (some circuits I've seen iirc are powerd from the pc not the car)

Nah what I meant is the actual ALDL communication line, This line run at 4.4 - 5 volts. For VN/VP's, the comms line is on the CEL ( Check engine light) line and is at 12volts.. sooo I would have thought we would see some smoke popping out of a standard aldl cable without some level conversion/resistors! Unless the chip has internal resistors ect but I wouldnt want to be stressing them anyways.

But yeah you are right, there are some devices that run off the cars or computers power. I feel the PC's output is a bit more reliable/stable due to a cars output is quite noise which could reflect in a 5v regulators output if its all over the place.

Anyway for anyone interested, see here for reference: Techedge

 

[Jxfwsf]

Ahh, same for vr, it's not actually @12v, the globe acts as a pull up resistor for the signal.

Just have to remember to keep the cable short between the plug and device, with the homebrew circuit there is filter capacitors on the power feed, if built properly and a good ground is used it should be fine (can always use ferrite cores n shielded cable but I've never had to)

 

[TazzI]

Just a couple questions I seem to keep getting, for those asking about tuning, read below!

For those asking about how to custom tune there V6's, you need to head over the PCMHacking.net, and read the documents over there! I also advise to pay a small fee to get someone to custom tune your car using your cars calibration data!

Also, you cannot tune your V8's or VZ/VE cars using an ALDL cable, these communicate over a different protocol (language) and require special hardware! Hence the VERY small amount of commercial tuning software available (HPtuners and EFIlive)

If you have questions, post them up in the thread since others may be looking for the same answer too!

 

[theghostoftime1978]

hi guys, just had a look at the efilive site, ive noticed there is version 8 on there now, can that work on vt v6

 

[TazzI]

hi guys, just had a look at the efilive site, ive noticed there is version 8 on there now, can that work on vt v6

Only efilive V4 works for ALDL cars, so that would be your VT V6.

Version8 is for OBD2 cars (Not ALDL), and will require their special hardware/cables for tuning and diagnostics.

 

[TazzI]

If you are getting an error saying "COM1 Not Available" or "Cannot connect to COM1". This is because your ALDL cable is more then likely not on "COM1".
You need to open up the settings/preferences in efilive/tunerpro and change the comport to your cables comport.

And heres a few Q/A's that Iv had alot recently:

Q: How do I know which comport is my ALDL Cables?
A: Quickest way is to look at the comports available with the cable plugged in, then unplug cable and check again. This can also be done through "Device Manager"

Q: I get alot of weird data and the gauges spaz out when I connect to tunerpro?
A: Make sure that you have the correct vehicle/definition file loaded up and make sure it is the most recent version. Otherwise software may have a hard time syncing up or may be trying to display for the wrong vehicle!

 

[junkiehunter]

is it possible to program the key remotes with this? my old one chucked a wobbly and refused to start my car, but with the black part removed i was able to get it going.

 

[TazzI]

is it possible to program the key remotes with this? my old one chucked a wobbly and refused to start my car, but with the black part removed i was able to get it going.

Technically, if you had the know how. Yes you could use an ALDL cable. But, theres currently no software that can do this

 

[junkiehunter]

a bit more messing around with it and ive discovered that i have to press the unlock button while turning the key, the key also will not open the doors remotely.

 

[j_ds_au]

Nah what I meant is the actual ALDL communication line, This line run at 4.4 - 5 volts. For VN/VP's, the comms line is on the CEL ( Check engine light) line and is at 12volts.. sooo I would have thought we would see some smoke popping out of a standard aldl cable without some level conversion/resistors! Unless the chip has internal resistors ect but I wouldnt want to be stressing them anyways.

Exactly. Unless the ALDL cable has been specifically designed for 12V signal levels, at the very best, you'd be injecting current into the static protection diodes of the UART-USB bridge chip's RX input via some series resistor, potentially overstressing it and even your PC. You'd better check with the vendor first to see it is safe to do this.

The other risk, which is easily overlooked (even by the vendor), is that the transistor on the TX part of the circuit will not be designed to drive the surge (cold) current of the CEL bulb. So if you accidentally run software that tries to transmit to the ALDL, you'll likely blow the TX circuitry, which may then impact on the RX circuitry (since they are tied together on a common data line), so the whole thing then doesn't work.

A purpose-designed ALDL cable for VN/VP will be designed for 12V signal levels and won't have TX circuitry to blow up. (At the moment, I'm considering designing and making such a cable to sell on eBay, but I'm not sure if there's enough demand to justify the effort.)

Joe.