Headlamp Switch: Description and Operation
CIRCUIT OPERATIONHeadlamp Switch Illumination
The illumination lamp is controlled by the dimmer switch. Power for the lamp is supplied on circuit E2. This circuit is protected by a 4 amp fuse in cavity 2 of the fuse block.
Power for the fuse is supplied on circuit E1 from the headlamp switch. This circuit is HOT when the headlamp switch is in the PARKING lamp or ON position.
Battery voltage for this portion on the headlamp switch is supplied on circuit F34 from the 20 amp fuse in cavity 11 of the fuse block. This fuse is HOT at all times.
Headlamp Switch In On Position (Low Beam Operation )
When the headlamp switch is in the ON position, the F34 circuit, from the Power Distribution Center (PDC), circuit connects to circuit L94. Circuit L94 connects to the LOW beam relay located in the PDC, coil side. With this input to the relay the contacts in the relay CLOSE connecting circuits A3 and L4. The A3 circuit is HOT at all times and protected by a 20 amp fuse in cavity 18 of the PDC.
Circuit L4 is double crimped at the relay and connects to separate fuses in the PDC.
Fuse 10, a 10 amp in the PDC, powers the right LOW beam headlamp on circuit L44. On vehicles built for sale in Canada, the L44 circuit is spliced and provides an input to the Daytime Running Lamp (DRL) module.
Fuse 9, a 10 amp in the PDC, powers the left LOW beam headlamp on circuit L43.
Headlamp Switch In The On Position (High Beam Operation)
When the headlamp switch is in the ON position and the operator selects HIGH beam operation circuit L94, from the headlamp switch, is connected to circuit G34 through the dimmer switch. Circuit G34 connects from the dimmer switch to the HIGH beam relay located in the Power Distribution Center (PDC).
With this input to the relay the contacts in the relay CLOSE connecting circuits L20 and L3. The L20 circuit is protected by a 20 amp fuse located in cavity 17 of the PDC. Circuit L3 connects from the relay to the HIGH beams of the headlamps.
On vehicles built for sale in Canada, the L3 circuit is spliced and provides an input to the Daytime Running Lamp (DRL) module.