Dakota 4WD V6-239 3.9L Magnum (1996)
Daytime Running Lamp Control Unit: Description and Operation
CIRCUIT OPERATION
On vehicles built for sale in Canada, the low-beam headlamps operate when the ignition switch is in the RUN position.
When the ignition switch is in the RUN position, it connects circuit A1 from fuse C in the Power Distribution Center (PDC), to circuit A21.
Circuit A21 is double crimped at a fuse block bus bar and supplies power to the Daytime Running Module (DRL) module.
Circuit L20 from the headlamp switch connects to DRL module. Circuit L20 is HOT at all times.
The DRL module receives the vehicle speed sensor input from circuit G7. Circuit G34 provides power for the high beam indicator lamp in the
instrument cluster and connects to the DRL module.
Circuit L4 powers the low beams of the left and right headlamps. When the headlamp switch is OFF, the DRL module powers the low beams on
circuit L4. When the headlamps are ON, the multi-function switch powers the low beams on circuit L4.
Circuit L3 feeds the high beams of the headlamps and connects to DRL module. When the operator flashes the headlamps with the stalk of the
multi-function switch, the DRL senses voltage on circuit L3. When it senses voltage on circuit L3, the DRL module stops supplying power to the
low beams on circuit L4.
Circuit Z1 provides ground for the DRL module.
