On my 2004 325ci i replaced the Safety cut off terminal (accident) and there is a wiring harness that leaves the (+) terminal and goes to a fuse box above the battery.
The harness has 2 black cables and they are connected on a yellow plug.
On the other side. Where they come from, there is a brown and blue wire. Can anyone trace them and tell me wich one goes where?


I cannot find a new harness to buy... HELP!! :help

anyone? :(

typically yellow or orange plugs mean airbag related. Not sure what components your SRS system as but Im assuming its rear impact sensors? Try Realoem.com see if it helps much

The two small wires (blue and brown) actually delivers a firing signal to the BST (battery safety terminal) w/c has a powder charge like an airbag during an accident to disconnect the positive battery terminal from the main cable. Emergency lights remain powered up
but the starter, engine, fuel pump, etc. are unpowered to minimize the possibility of
fires.
When you buy a new BST repair cable from a dealer, the 2 wires connecting to the blue/brown wires are built-in to the cable. If you have a new one just tell me and I will tell you how to connect the replacement cable and terminal properly.
If you just reconnect the BST that has fired already, a fault code and checklight will
persists since the car's computer would recognize the open circuit in the firing mechanism of the BST. And knowing which connects to which is irrelevant since the wiring is already useless and best left unattached.

Thank you so much for your responce techvet.
This picture shows the old one. I have replaced it with a new one but the 2 wires are missing the other plug.
Here is the picture showing the wires
I really appreciate your help,
Chris.