CHECK ENGINE Light/Malfunction Indicator Light (MIL)

WARNING: This page is about a different car, the 1995 Ford Explorer and 1995 Ford Aerostar. However, it is still accessible from the selected car via links, so may be relevant.

Turn ignition on. Connect a jumper wire between Self-Test Input (STI) pigtail and signal return (SIG RTN) terminal of Data Link Connector (DLC). See Fig 1. Go to KOEO SELF-TEST.

Fig 1: Self-Test Equipment Hook-Up For CHECK ENGINE Light/ Malfunction Indicator Light (4.0L)

Courtesy of FORD MOTOR CO.