Recommended splicing method - Solder (For 16 AWG/1.0 and Smaller Diameter Wire Only)

WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, and 2011 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Cut and splice one circuit at a time noting the original wire to connector pin locations This will avoid miss-connections.

Disconnect battery ground cable.
Strip wires to appropriate length.

Fig 1: Identifying Strip Wires To Appropriate Length
Courtesy of FORD MOTOR CO.
Install heat shrink tubing.
Twist wires together.
Solder wires together.
NOTE: Use rosin core mildly-activated (RMA) solder. Do not use acid core solder.

NOTE: Use heat shrinkable tubes marked with ES-1 (16-22 AWG/0.5-1.0mm) or ES-2 (10-18 AWG/0.8-5.0mm) to seal wire splice.

Fig 2: Identifying Solder Wires And Shrinkable Tubes Marked
Courtesy of FORD MOTOR CO.
Evenly position heat shrink tubing over wire repair.
NOTE: Overlap tubing on both wires.

Fig 3: Identifying Overlap Tubing On Both Wires
Courtesy of FORD MOTOR CO.
Use shielded heat gun to heat the repaired area until adhesive flows out of both ends of heat shrink tubing.
NOTE: On smaller wires, use pliers to gently squeeze the ends of the heat shrink sleeve (while heat shrink is still warm) to ensure a tight fit and close any air gaps
Reconnect battery ground cable.

Fig 4: Identifying Shrink Tubing And Wires
Courtesy of FORD MOTOR CO.