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For 1990-2009 cars only

Exterior Lights Circuit Description P32

Headlamps Circuit Description

Voltage is available at all times to the headlamp switch from the junction block through CKT 2 (RED). Within the headlamp switch is a circuit breaker which resets automatically. The circuit breaker opens upon heating due to an overcurrent condition. With the circuit breaker open, current stops, and the circuit breaker's thermal element cools. When the thermal element is sufficiently cooled, the circuit breaker closes.

The 3-position headlamp switch has the following positions:

    • An off position
    • A parking lamps position
    • A headlamps position

When the switch is in the headlamps position, voltage is available on CKT 10 (YEL) to the headlamps dimmer switch. The headlamp dimmer switch is part of the multifunction switch on the steering column. By pulling the multifunction switch lever up along the axis of the steering column, the switch changes selections between the high beam and the low beam.

With the selection of the low beams, voltage is supplied to the low beam of the left headlamp, cavity A, and then to the low beam of the right headlamp, cavity A, on CKT 12 (TAN). With the selection of high beams, voltage is supplied to the high beam on the left headlamp, cavity B, and then to the high beam of the right headlamp, cavity B, on CKT 11 (LT GRN). Ground is supplied for both headlamps through G101, G102, or G107.

On vehicles equipped with dual rectangular headlamps, when the headlamps dimmer switch is in the high position, voltage is supplied to both outer headlamps before being supplied to their respective inner headlamps. The outer and inner headlamps are all grounded through G101, G102, or G107.

CKT 11 (LT GRN) also provides high beam voltage to the instrument cluster for the illumination of the high beam indicator lamp. Ground is available through CKT 451 (BLK) to G108.

DRL Circuit Description

The headlamps switch provides constant voltage to the switch side, cavity 87, of the daytime running lamps (DRL) relay through CKT 640 (ORN). Voltage is supplied to the coil side of the DRL relay, cavity 85, from the GAUGES fuse when the ignition is in the RUN or START position. Ground is provided for the relay through CKT 592 (LT GRN/BLK) to the normally closed DRL relay control switch, cavity G, at the DRL module. When the DRL relay is energized, the relay contacts close and voltage is supplied to the low beam of the left headlamp through cavity C. Voltage is supplied to the low beam of the right headlamp, cavity B, through the left headlamp, cavity B. The right headlamp is grounded at G101, G102, or G107 in order to complete the circuit.

On vehicles equipped with dual rectangular headlamps, the energized DRL relay provides voltage to the left inner headlamp at cavity B and the second DRL relay at cavity 85. When grounded through CKT 150 (BLK) at G101, G102, or G107, the second DRL relay energizes and closes the switch contacts. Voltage is supplied from the left inner headlamp, cavity A, to the right inner headlamp, cavity A, and to cavity 30 on the second DRL relay. The inner headlamps illuminate when ground is established at G101, G102, or G107 through CKT 150 (BLK) from the right inner headlamp, cavity B. The inner headlamps are in series with each other and have reduced intensity. Voltage is supplied to the high beams of the left and right outer headlamps by the second DRL relay. The outer headlamps illuminate when ground is established at G101, G102, or G107 through CKT 150 (BLK). The outer headlamps are in series with the left inner headlamp and have reduced intensity.

When the headlamp switch is in the head position, the voltage is directed to the headlamps dimmer switch and the headlamp switch input at the DRL module through CKT 10 (YEL). The module opens the contacts at the DRL relay control switch and this interrupts the path to ground. The contacts at the DRL relay open and the daytime running lamps are shut off. This interruption in the ground path also turns the DRL indicator off.

With the headlamp switch in the head position and headlamps dimmer switch is in the low position, voltage is available to the left low beam headlamp, cavity A, and then to the right low beam headlamp, cavity A, through CKT 12 (TAN). G101, G102, or G107 supply ground to the right headlamp through CKT 150 (BLK) and complete the circuit. On vehicles equipped with dual rectangular headlamps, G101, G102, or G107 supply ground to both headlamps.

When the headlamps dimmer switch is moved to the high position, voltage is available to the left high beam headlamp and then to the right high beam headlamp through CKT 11 (LT GRN). G102, G101, or G107 supply ground to the right headlamp through CKT 150 (BLK) and complete the circuit. On vehicles equipped with dual rectangular headlamps, voltage from the headlamp dimmer switch is supplied to the inner headlamps at cavity A and the second DRL relay at cavity 30 through CKT 11 (LT GRN). G101, G102 and G107 provide a direct ground for the right inner headlamp through CKT 150 (BLK). Ground for the left inner headlamp through CKT 150 (BLK) is provided through the second DRL relay. This energizes the relay and the switch contacts close. Voltage is then supplied to the left outer headlamp, cavity B, through CKT 11 (LT GRN) and then to the right outer headlamp, cavity B. Each headlamp is separately grounded through CKT 150 (BLK) at G102, G101, or G107.

With the headlamps dimmer switch in the high position, voltage is also available to the high beam input at the DRL module. This signal prompts the DRL to supply battery voltage to the Hi Beam indicator at the instrument cluster. Ground G108 completes the circuit and the indicator illuminates.

Park, Tail, Marker, and License Lamps Circuit Description

Voltage is available through the TAIL LPS fuse to the headlamps switch at all times. With the headlamp switch in the park or head position, voltage is available to the following components through CKT 9 (BRN):

    • The park lamps
    • The tail lamps
    • The front sidemarker lamps
    • The rear sidemarker lamps
    • The license lamps

On export vehicles, voltage is available through the TAIL LPS fuse to the headlamp panel dimmer switch, cavity H, at all times. With the headlamp switch in the park or headlamp position, voltage is available through CKT 9 (BRN) to the following fuses and components:

  1. The FRONT PARK LPS fuse to the park lamps and the front marker lamps through CKT 964 (BRN) and CKT 9 (BRN)
  2. The MARKER/LICENSE LPS fuse to the license lamps through CKT 914 (GRY)
  3. The LH TAIL LPS fuse to the left tail lamps and rear marker lamps through CKT 912 (PPL)
  4. The RH TAIL LPS fuse to the right tail lamps and rear marker lamps through CKT 913 (DK BLU).

For all vehicles, the park, tail, and license lamps are all case grounded. The front sidemarker lamps ground through the turn signal lamps and the rear sidemarker lamps ground through G 401.

Stoplamps Circuit Description

Voltage is available at all times through the STOP/HAZ fuse to the stoplamp switch. With the depression of the brake pedal, the contacts in the stoplamp switch close and voltage is available through the turn signal switch to the left stoplamp, CKT 18 (YEL) and the right stoplamp, CKT 19 (DK GRN). Both lamps are case grounded.

Turn Signal Lamps Circuit Description

With the ignition switch in the RUN position, voltage is available through the TURN-B/U fuse and the turn signal lamps flasher to the only closed contact of the hazard flasher switch within the turn signal switch.

With the turn signal switch in the left turn position, voltage is available to the turn signal lamp and left turn indicator on CKT 14 (LT BLU) and the stoplamp on CKT 18 (YEL) . With the turn signal switch in the right turn position, voltage is available to the turn signal lamp and right turn indicator on CKT 15 (DK BLU) and the stop lamp on CKT 19 (DK GRN). The turn signal lamps are case grounded and the indicator lamps are grounded to G108.

The lamps immediately illuminate and begin flashing when the current flow heats the timing element in the flasher. The timing element repeatedly opens and closes the circuit.

With the turn signal switch inactive, voltage to the turn signal lamps runs through the front marker lamps. When the turn signal switch is activated, a second circuit is used in order to power the turn signal lamps. The ground path for the marker lamps is interrupted and the marker lamps will not light. As the turn signal lamps flasher opens and closes the circuit, the front marker lamps light opposite to the turn signal lamps.

Hazard Flasher Circuit Description

Voltage is available at all times through the STOP/HAZ fuse and the hazard lamps flasher to the normally open contacts of the hazard flasher switch within the turn signal switch. With the hazard switch in the on position, voltage is available to the following components:

    • The instrument cluster
    • The front marker lamps
    • The turn signal lamps
    • The stop/turn signal lamps

All of the turn lamps and the turn indicators flash on and off.

Backup Lights Circuit Description

When the ignition switch is in the RUN position, voltage is available through the AUTO APPLY fuse to the park/neutral position and backup lamps switch on CKT 639 (PNK). With the transaxle in reverse, voltage is available to the left and right backup lamps, which are case grounded, on CKT 24 (LT GRN).

Interior Lamps Dimming Circuit Description

Voltage is supplied to the headlamps switch, cavity E, at all times by the TAIL LPS fuse. The headlamps switch provides voltage to the IP lamps dimmer switch in the park and head position through CKT 9 (BRN). With the contacts of the panel lamps switch closed, voltage is supplied to the INSTR-LPS fuse through CKT 44 (DK GRN). This fuse protects CKT 8 (GRY) in the event of a short to ground or an overload and supplies voltage to the seat belt and lamps alarm module, the transmission range lamp, and the illumination lamps at the instrument cluster. Rotation of the IP lamps dimmer switch toward the full OFF position (within 5 degrees of the end of rotation) reduces voltage until the current is so low that the lamps do not illuminate.

The seat belt and lamps alarm circuit operation is found in Audible Warnings Circuit Description in Instrument Panel, Gauges, and Console. The transmission range lamp is case grounded and the illumination lamps are grounded through G108.

The HORN-DM fuse provides voltage on CKT 40 (ORN) to cavity A of connector C210 for the body builder installed dome lamp. The ground is provided by the following path:

  1. CKT 156 (WHT) from C210, cavity B, to the IP lamps dimmer switch.
  2. CKT 250 (BLK) from the IP lamps dimmer switch to ground G200

On export vehicles, voltage is supplied to the headlamp panel dimmer switch, cavity H, at all times by the TAIL LPS fuse. Voltage is also supplied to the headlamp panel dimmer switch, cavity D, in RUN and START by the GAUGES fuse. With the headlamp panel dimmer switch in the park position, voltage is supplied to the exterior lights through CKT 9 (BRN), the INSTR LPS fuse through CKT 44 (DK GRN), and the dimmer switch lamp. The INSTR LPS fuse supplies voltage to the following components:

    • The seat belt
    • The lamps alarm module
    • The transmission range lamp
    • The illumination lamps at the instrument cluster

The seat belt and lamps alarm circuit operation is found in Audible Warnings Circuit Description in Instrument Panel, Gauges, and Console. The transmission range lamp is case grounded and the illumination lamps are grounded through G108. The dimmer switch lamp is grounded through G200.

The HORN-DM fuse provides voltage on CKT 40 (ORN) to the DOME OVERRIDE switch in the headlamp panel dimmer switch, cavity L. These contacts are normally closed and provide voltage to connector C210 for the body builder installed dome lamp. The ground is provided by the following path:

  1. CKT 156 (WHT) from C210, cavity B, to the headlamp panel dimmer switch, cavity M
  2. The closed contacts of the dome lamp switch
  3. CKT 250 (BLK) from the headlamp panel dimmer switch, cavity R, to ground G200

Exterior Lights Circuit Description P42

Headlamps Circuit Description

Voltage is available at all times to the headlamp switch from the junction block through CKT 2 (RED). Within the headlamp switch is a circuit breaker, which resets automatically. The circuit breaker opens upon heating due to an overcurrent condition. With the circuit breaker open, current stops, and the circuit breaker's thermal element cools. When the thermal element is sufficiently cooled, the circuit breaker closes.

The 3-position headlamp switch has the following positions:

    • An off position
    • A parking lamps position
    • A headlamps position

When the switch is in the headlamps position, voltage is available on CKT 10 (YEL) to the headlamps dimmer switch. The headlamp dimmer switch is part of the multifunction switch on the steering column. By pulling the multifunction switch lever up along the axis of the steering column, the switch changes selections between the high beam and the low beam.

With the selection of the low beams, voltage is supplied to the left headlamp, cavity C, and then to the right headlamp, cavity C, through CKT 12 (TAN). With the selection of high beams, voltage is supplied to the left headlamp, cavity B, and then to the right headlamp, cavity B, through CKT 11 (LT GRN). Ground is supplied for both headlamps through G200.

CKT 11 (LT GRN) also supplies high beam voltage to the instrument cluster for the illumination of the high beam indicator lamp. Ground is available through CKT 451 (BLK) to ground G103.

DRL Circuit Description

The headlamps switch provides constant voltage to the switch side, cavity 87, of the daytime running lamps (DRL) relay through CKT 640 (ORN). Voltage is supplied to the coil side of the DRL relay, cavity 85, from the GAUGES fuse when the ignition is in the RUN or START position. Ground is provided for the relay through CKT 592 (LT GRN/BLK) to the normally closed DRL relay control switch, cavity G, at the DRL module. When the DRL relay is energized, the relay contacts close and voltage is supplied to the low beam of the left headlamp through cavity A. Voltage is supplied to the low beam of the right headlamp, cavity C, through the left headlamp, cavity C, and the right headlamp is grounded at G200 in order to complete the circuit.

When the headlamp switch is in the head position, the voltage is directed to the headlamps dimmer switch and the headlamp switch input at the DRL module. The module opens the contacts at the DRL relay control switch and this interrupts the path to ground. The contacts at the DRL relay open and the daytime running lamps are shut off. This interruption in the ground path also turns off the DRL indicator.

With the headlamp switch in the head position and headlamps dimmer switch in the low position, voltage is available, first, to the left low beam headlamp and then to the right low beam headlamp. G200 supplies ground to the right headlamp and completes the circuit.

When the headlamps dimmer switch is moved to the high position, voltage is available, first, to the left high beam headlamp and then to the right high beam headlamp. G200 supplies ground to the right headlamp and completes the circuit.

With the headlamps dimmer switch in the high position, voltage is also available to the high beam input at the DRL module. This signal prompts the DRL to supply battery voltage to the Hi Beam indicator at the instrument cluster. Ground G108 completes the circuit and the indicator illuminates.

Park, Tail, Marker, and License Lamps Circuit Description

Voltage is available through the TAIL LPS fuse to the headlamps switch at all times. With the headlamp switch in the park or head position, voltage is available to the following components through CKT 9 (BRN):

    • The park lamps
    • The tail lamps
    • The marker lamps
    • The license lamps

The park and marker lamps are grounded through G200. The tail lamps and the license lamps are case grounded.

Stoplamps Circuit Description

Voltage is available at all times through the STOP/HAZ fuse to the stoplamp switch. With the depression of the brake pedal, the contacts in the stoplamp switch close and voltage is available through the turn signal switch to the left stoplamp, CKT 18 (YEL) and the right stoplamp, CKT 19 (DK GRN). Both lamps are case grounded.

Turn Signal Lamps Circuit Description

With the ignition switch in the RUN position, voltage is available through the TURN-B/U fuse and the turn signal lamps flasher to the only closed contact of the hazard flasher switch within the turn signal switch.

With the turn signal switch in the left turn position, voltage is available to the turn signal lamp and left turn indicator on CKT 14 (LT BLU) and the stoplamp on CKT 18 (YEL) . With the turn signal switch in the right turn position, voltage is available to the turn signal lamp and right turn indicator on CKT 15 (DK BLU) and the stoplamp on CKT 19 (DK GRN). The turn signal lamps are grounded to G200. The indicator lamps are grounded to G108. The stoplamps are case grounded.

The lamps immediately illuminate and begin flashing when the current flow heats the timing element in the flasher. The timing element repeatedly opens and closes the circuit.

With the turn signal switch inactive, voltage to the turn signal lamps is supplied through the marker lamps. When the turn signal switch is activated, a second circuit is used in order to power the turn signal lamps. The ground path for the marker lamps is interrupted and the marker lamps will not light. As the turn signal lamps flasher opens and closes the circuit, the marker lamps light opposite to the turn signal lamps.

Hazard Flasher Circuit Description

Voltage is available at all times through the STOP/HAZ fuse and the hazard lamps flasher to the open contacts of the hazard flasher switch within the turn signal switch. With the hazard switch in the on position, voltage is available to the instrument cluster, the turn signal lamps and the stop/turn signal lamps. All of the turn lamps and the turn indicators flash on and off.

The front marker lamps flash in the hazard on position in the same manner the hazard lamps flash in the turn right or turn left position with the headlamps switch in park or head.

In the HAZARD position, the circuit is always open, and the turn lamps flasher controls the lamps.

Backup Lights Circuit Description

When the ignition switch is in the RUN position, voltage is available through the TURN B/U fuse to the backup lamp switch (manual transmission) or the park/neutral position and backup lamps switch (automatic transmission) on CKT 141 (BRN). With the transaxle in REVERSE, voltage is available to the left and right backup lamps, which are case grounded, on CKT 24 (LT GRN).

Interior Lamps Dimming Circuit Description

Voltage is supplied to the headlamps switch at all times by the TAIL-LPS fuse. The headlamps switch provides voltage to the IP lamps dimmer switch in the park and head position. With the contacts of the panel lamps switch closed, voltage is supplied to the INSTR-LPS fuse. This fuse protects CKT 8 (GRY) in the event of a short to ground or an overload. This fuse supplies voltage to the seat belts alarm module, the transmission range lamp, and the illumination lamps at the instrument cluster. Rotation of the IP lamps dimmer switch toward the full OFF position (within 5 degrees of the end of rotation) reduces voltage until the current is so low that the lamps do not illuminate.

The seat belt alarm circuit operation is found in Audible Warnings Circuit Description in Instrument Panel, Gauges, and Console. The transmission range lamp is case grounded. The illumination lamps are grounded through G108.

The HORN-DM fuse provides voltage on CKT 40 (ORN) to cavity G of connector C207 for the body builder installed dome lamp. The ground is provided by the following path:

  1. CKT 156 (WHT) from C207, cavity A, to the IP lamps dimmer switch
  2. CKT 250 (BLK) from the IP lamps dimmer switch to ground G200