Grande Punto T-Jet 2009 and ELM327 BT Interface

[PizzaPooch]

Hi everyone,

after reading a bunch of threads regarding FES and cheaper modules, I went for a relatively common Bluetooth Interface (http://www.amazon.de/gp/product/B006CFX ... 00_details).
A quick test in my car showed, that I have no connection to the Can Bus. Expecting this, hence I read the thread "Faulty ELM 327 Interfaces...", I opened my Interface, compared it to the pics in the thread, and unsoldered R04.

Here's a picture, before the modification:


With the Interface and good thoughts in mind, I tested it in the car again. Same problem. I am able to connect to the motor control module (the first one). I ran a few tests (fuel pump, a/c fan speed,...) and they worked well.
But most of the other modules (in fact those, who need an adapter cable), won't let me in (ELM 327 -> ECU error).

Although there is a good listing under "Supported Vehicles", it's not clear for me, what to do next.
Should I buy a yellow adapter cable (number 3) or is it possible to modify just the interface to function with all control modules.
According to the "Supported Vehicles" page, the latter is a no go:
"DO NOT USE MODIFIED INTERFACES WITH SHORT CIRCUIT BETWEEN PINS 1 AND 9 ON GRANDE PUNTO, PUNTO EVO, FIAT 500, DOBLO(152), DOBLO(263), ALFA MITO, GIULIETTA, YPSILON 2011!"

I don't want to make a mistake here, but I don't want to buy an adapter cable, if this can be done just with the Interface.

Thank you in advance!

Greetings,
Chris

[Juggers2k]

Yes, you will need an adaptor 3 cable.

Adaptor 3 diverts both CAN lines from those used by the high-speed CAN systems (pins 6 & 14 on the port - engine etc), to those used by the low-speed CAN systems (pins 1 & 9).

If you modify the interface cable you'll be sending all CAN commands to both CAN buses, which could cause problems.

The warning note on the supported vehicles list relates to using an Adaptor 1 cable with a Grande Punto.
This is because the low-speed CAN protocol uses pins 1 and 9 for the CAN data lines.

Adaptor 1 is for use with cars based on K-line diagnostics and shorts (among others) pins 1 and 9 together to support different systems. If you plug that cable into a slow-CAN car, it will short the 2 CAN data lines together.

[PizzaPooch]

Excellent! Thank you for your detailed reply. This helps me (and probably others) a lot

[djbase]

Idd, that was a good question I was wondering myself.

So to be clear : you need to buy an adaptor cable 3 ? Or can you patch the original ELM 327 bluetooth module ?

Also where can you buy the adaptor cable 3 ?

Tnx !

It's for my alfa giulietta.

Djbase

[Juggers2k]

Idd, that was a good question I was wondering myself.

So to be clear : you need to buy an adaptor cable 3 ? Or can you patch the original ELM 327 bluetooth module ?

Also where can you buy the adaptor cable 3 ?

Tnx !

It's for my alfa giulietta.

Djbase

Read my earlier reply.
The GP and Guilietta have 2 different speed CAN buses, running on different pins in the port. The yellow adaptor diverts the can lines from the fast-CAN pins to the slow-CAN pins, to cover the other systems.
If you made that link permanently you'd be transmitting to both buses at once, which could cause problems.

So you either need to add a switch to your ELM327 so you can switch between the high and low-speed CAN pins, or buy an adaptor 3 cable.

As for where to buy - the best place to start looking is the distributor list on the main FES website.