Exterior Lighting System How It Works . . . I The headlight switch is constantly powered. I At the lirst detent (stop), the parking lights and marker lights operate. I Full extension oi knob operates headlights. I Rotating the knob brightens and aims instrument cluster lighting and operates dome light. I The switch has an internal circuit breaker for the headlights Circuit and one for the parking/marker lamp circuit These circuit breakers are automatic resetting, Trouble-Shooting A Single Lamp Fails lionly one lamp Is not operating. the likely causes are . t . I burned out lamp I lamp not completely in socket I lamp connector not properly connected or corroded I lamp holder not grounded. To find the cause at a single lamp failure . . . I remove the lamp and inspect fora broken lilament (burned out) I install new lamp, test it to make sure it works I turn on circuit it the light still doesn't work. do the tollowlng (In order) until the circuit works . . . I if a fused circuit, check the luse I check lamp holder lor corrosion I check lamp holder for ground I check leed for solid connections and corrosion Headlights Fail, Parking Lights Operate Make sure the switch is pulled out completely . . . I then operate the dimmer switch. ltthere is still no headlights . . . I check for power at dimmer switch connectortermtnal ol wtre 15 iylbk) it there is no power at dimmer switch connector terminal at wire 15 (y/bk) . t . I check for power at light switch terminal ol wire 285 (or) Ii there is no power at light switch terminal at wire 285 (or) . . . I replace the light switch It there is no power at dimmer connector terminal oi wire 15 (y/bk) . . . I check lor power at other two switch terminals if neither oi these terminals have power . . . I replace dimmer switch It either oi these terminals have power. periorrn the following procedures (In order) and make neccessary repairs until the problem is corrected . . . I check the wiring from the hot terminal oi the dimmer switch to headlights I check to splice 801, located behind the instrument cluster I check headlight bulb filaments for continuity with the connectors plugged in I check that each lamp socket is properly grounded Checking dlmmer swllch letmtnai oi wire 15 iyi bki lor power Checking ltghiswilch iemunal ol wire 2&5 um lor power Headlights Operate Only In High or Low Beam I place dimmer switch so that you can operate it by hand I insert lest light on terminal of wire 12 (gr/bk) oldimmer swrtch I operate dimmer switch by hand several times I insert test light on terminal oi wire 13 (r/bk) oldimmar switch I operate dimmer switch by hand several times Checking tenninalsolwtres 15 my) and 235 (on It test light does not flash on and on as dimmer button is pushed . . . I replace dimmer switch. it high beam indicator comes on . . . I check power to terminal olwire 13 (r/ bk) Headlight Fails to Operate for High and Low Beam on One 3 de Only Pertorm these checks (In order), making necessary repairs until situation ls corrected . . t I check for ground at malfunctioning bulb I remove bulb I check bulb laments for continuity (no continuity indicates a burned out bulb. check bulb socketground terminal at ground Headlights Operate; Parking, Side Marker and License Plate Lights Fail II power Is not present at terminal of wire 25 (bk/o) , ., I check black and orange wire to luse link I inspect iuse link I check black and orange wire to battery It power is presentat terminal otwire 25 (bk/o) . . . I check terminal tor damage and repair or replace as necessary I replace light switch, iiterminal Is OK. All Exterior Lights Fail A quick check . . I make sure light switch is pulled completely out. "this tails to opemte lights, conduct these tests (In order) until lights COME Ol'l . t . I check ior solid connection at connector and light switch I check for power at terminal olwire 25 (bk/o) oi headlight switch Periorm these checks (in order), making necessary repairs until situation is corrected , . . I check light switch connector tor damage at terminal with the brown wire(s). I repair damage or replace connector. If there Is no damage. .. I check brown wire for continuity and power ll brown wire is O.K. I replace headlight switch. i3 1: 7 l5 rly .. :1 Dimmer Switch Connector 25 mm 255 m t5 ry Headlight switch Connector