Air Bag Connectors

450 Fortwo

Both the steering wheel and passenger airbag use the same connector.

Amphenol CA252

Assuming the link stays live, this connector looks like item 5 here. Have a look around AliExpress and search for hairspring plug and then visually match it to what you need.

451 Fortwo

The steering wheel airbag uses an FCI A05154525

For the passenger airbag, I don’t know yet but it would surprise me if it was similar to the green/orange one above but yellow with an orange tab. Probably an FCI 05154526. If you know for sure, let me know to save me having to check.

452 Roadster

The steering wheel airbag has a different connector to the passenger side airbag.

The steering wheel airbag connector is an Amphenol CA252

Assuming the link stays live, this connector looks like item 5 here. Have a look around AliExpress and search for hairspring plug and then visually match it to what you need.

The passenger side airbag has a yet unknown connector.

It has a hinged tab that unlocks the connector.

If you know what it is, let me know.

453 Fortwo & Forfour

The 453 has different connectors for the main dashboard airbags. The knee airbag connector looks like this. It’s a Delphi connector.

Each of the connectors have different colours and are keyed differently so you can’t plug them into the wrong airbag.

However, if the airbag blows, they often create enough heat to melt the connector so it cannot be reused. When you try to disconnect the airbag connector, the tab will snap because…

…the other side has melted into a single piece of plastic. It shouldn’t need saying but, this cannot be reused. You have to cut the old one off and splice a new replacement in.

This is what the passenger’s side airbag connector should look like. Notice the keyed plastic tab is different to…

…the knee airbag connector. Just buy a replacement connector that’s the same colour and the same design.

Although they are Delphi branded, I’m convinced that there are very few actual connector manufacturers and the same company owns all the big names. Delphi, Tyco, AMP, JST etc, all seem to put their brand name on the same connector types.

They look to be JST SQXW squib connectors.

If you go onto AliExpress and type in Airbag Connectors or Hairspring Plug, you’ll find some similar ones.

Keyed Connections

Although a black connector one plug into a teal connection, if you cut the plastic tab out from inside the connector, it’ll fit either. It’s not ideal but it’s what I had to do as it’s all I had.

Splicing The New Connector

Cut the old connector off close to the melted connector. Slide some heat shrink tube onto each wire, bare the copper from the existing wire and the new connector. Twist the connections together.

Flow the twisted copper with solder to bind them securely together.

Slide the heat shrink tubing over the joins…

…and then heat them to shrink the tube and protect your new connections.