Hi, does anyone know what the pins are on the Ford fiesta 1.0 ecoboost ODBC port?. On the top row of pins 1,3,6,8 are populated. On the bottom row 11,12,13,14 are populated. Pin 4 would normally be the chassis ground but doesn’t seem to be populated? 6 and 14 seem to be hi/low CAN as I get 60ohm resistance across them. Any help greatly appreciated.

On 4/11/2024 at 2:33 PM, boylin said:

Okay I’ve checked the resistance on the OBD port on the canbus wiring, I used the attached picture and all three canbus are showing 61ohms. 

The OBDII port is  standard on all vehicles fitted with one.

34 minutes ago, Outcycling said:

On the top row of pins 1,3,6,8 are populated. On the bottom row 11,12,13,14 are populated. Pin 4 would normally be the chassis ground but doesn’t seem to be populated?

You are looking at the socket the correct way up ?

Manufactures very often mount the socket upside down. You need to look at the shape of the socket, pins 1 and 8 are at the widest part, "the top" even if the socket is the other way up.

Yep, I think you are right. It’s upside down. But in that case I’m not getting 60ohms across the can which could be my error. Cheers.

It is weird. As yes the module is upside down but when I do a resistance across the MS can I’m getting 60ohms which seems unlikely as I believe each module on than can has a resistor. And when I do a test across the HS can I’m getting fluctuating results with the display flicking between 23 35 and 40ohms, I also saw it flick to 77 and over a hundred once. ?

57 minutes ago, Outcycling said:

But in that case I’m not getting 60ohms across the can

You can't be looking at the right connections. The canbus would still be the same.

There are only 2 resistors fitted to each of the networks. Each resistor is 120 ohms so when the canbus network is complete the reading is 60 ohms

5 minutes ago, Outcycling said:

I believe each module on than can has a resistor.

No, there are only 2 resistors per canbus system.

 

On 4/11/2024 at 8:54 PM, unofix said:

Yes, pretty much so. There is one 120 Ohm resistor fitted across each pair of canbus wires at the start and finish of the network. So in effect two 120 resistors are fitted in parallel. If there is a break in the wiring then you will only read across one of the resistors which would give a value of 120 instead of 60 Ohms.

 

In which case the HS CAN is faulty somehow.

That is exactly as I tested it unofix.

Are you testing the resistance with the battery disconnected?