Section 17-04: Lamps, Daytime Running
1994 Mustang Workshop Manual
DIAGNOSIS AND TESTING

Symptom Chart

ConditionPossible SourceAction
  • With Ignition Switch In RUN, Parking Brake Fully Released and the Headlamp Switch Off or in Parking Lamp Position: High Beams Are Not On At AllHigh Beams Are On At Full Intensity
  • Daytime running lights control is not installed.
  • Open or shorted circuitry.
  • Damaged daytime running lights control .
  • Check to see if daytime running lights control is connected. If loose or disconnected, inspect connector and reconnect daytime running lights control .
  • If the daytime running lights control is properly connected, Go to Pinpoint Test A.
  • With Ignition Switch OFF, Parking Brake Fully Released, and the Headlamp Switch OFF or in the Parking Lamp Position: High Beams Are On At Reduced Intensity
  • Damaged ignition switch .
  • Shorted wiring.
  • Damaged daytime running lights control .
  • With Ignition Switch in RUN, Parking Brake Applied, and the Headlamp Switch OFF or in the Parking Lamp Position: High Beams Are On At Reduced Intensity
  • Open wiring or poor ground.
  • Damaged parking brake signal switch and bracket .
  • Damaged daytime running lights control .
  • With Ignition Switch ON: High Beams Are On At Reduced Intensity
  • Damaged headlamp switch .
  • Damaged daytime running lights control .
  • With Headlamps in the High Beam Position: High Beams On, No Indicator in instrument panel
  • Burned-out bulb.
  • Open in wiring.
  • Damaged daytime running lights control .