Coil question - 92 535i

[Bill in MA]

Been looking at the Bentley and the coil on my EML equipped 5er. The manual only shows one wire going to the negative side of the coil (terminal 1), but there are two on my car. One wire goes to pin 1 on the DME connector and also splices into the diagnostic connector.

Anyone know the function of the second wire??


Thanks

Bill
92 535i turbo