Chassis Cab Snowplow Installation
Projector / Premium Hook-Up Instructions
09/01/2014
Snow Plow Hook Up for Projector Head Lamps.
Headlamps (Projector/Premium)
Each head lamp bulb circuit is independently pulse width modulated, (PWM) controlled by an electronic control module.
The low beam (projector) bulbs are halogen. When “high Beams” are selected, there is a Shutter that is opened by the
electronic control module allowing more light through from the low beam bulb. Also,Aa second incandescent bulb is also
turned on. The module monitors each bulb to detect failures. (Burned out bulbs) When a failure occurs, the “LAMP
OUT” telltale in the instrument cluster will illuminate whenever the ignition is in the run position. Therefore, the any
aftermarket wiring kits should use the following guidelines:
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Disconnection of the OEM headlamps will be interpreted by the electronic module as a burned out bulb
therefore, it is recommended that the aftermarket lamps utilize the OEM headlamp circuits.
Provide a means of allowing the customer to manually switch between the OEM headlamps and the aftermarket
headlamps. Connection of both the OEM and aftermarket lamps at the same time will cause the control module
to disable the circuit due to an overload condition and illuminate the “LAMP OUT” indicator in the instrument
cluster.
Also, assure that the OEM headlamps cannot be inadvertently disabled when the aftermarket lamps are
disconnected (i.e. when the snowplow is not on the vehicle).
Do NOT splice the right and left headlamp circuits together. Connection of both lamps to the same circuit will
cause the control module to disable the circuit due to an overload condition and illuminate the “LAMP OUT”
indicator in the instrument cluster.
The following is an outline of the headlamp circuits:
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The driver side low beam (halogen) circuit is L43, 20 AWG WT/DB (pin 5)
The driver side high beam (incandescent) circuit is L33, 20 AWG WT/LG (pin 7)
The driver side shutter control circuit is L300L, 20AWG LG/WT (pin 1)
The passenger side low beam (halogen) circuit is L44, 20 AWG WT/TN (pin 5)
The passenger side high beam (incandescent) circuit is L34, 20 AWG WT/GY (pin 7)
The passenger side shutter control circuit is L300R, 20AWG LG/WT (pin 1
TURN LAMPS (Projector/Premium)
Each turn lamp front driver, front passenger, rear driver, rear passenger, is independently controlled by an electronic
control module. The power circuits driving the front turn signal LED array’s do not have bulb out diagnostics. There is a
circuit board in the head lamp assembly that does diagnostics on the LED array. If a problem is detected, a signal is sent
back to the electronic control module on a separate feedback circuit. When a failure occurs, the “LAMP OUT” telltale in
the instrument cluster will illuminate whenever the ignition is in the run position.
In order to successfully connect the plow’s turn signal lamps to the vehicle’s wiring harness, the following must be done:
Both L60 and L61 need to be spliced in to in order to control a set of relays. The plow’s turn signal bulbs will be driven by
the relay’s contacts. (see schematic) The relay contact’s power source must be fused to battery feed.
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These relays are necessary for proper function of the turn signals while the plow lamps are attached to the
vehicle’s electrical system. Failure to do so may cause the front turn signals to be inoperable or intermittent.
The aftermarket park lamps cannot be wired directly to the vehicle’s circuits as the electronic control module is
not capable of driving an incandescent bulb.
The following is an outline of the turn signal circuits:
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The front driver lamp circuit is L61, 20 AWG WT/LG (pin 12)
The front driver feedback circuit is L551, 20 AWG TN/BR (pin 14)
The front passenger lamp circuit is L60, 20AWG WT/TN (pin 12)
The front passenger feedback circuit is L552, 20 AWG TN/OR (pin 14)
NOTE: The electronic module is only capable of detecting LED failure in the vehicles head lamp assembly.
Park Lamps (Projector/Premium)
The vehicle’s park/tail/license/marker/tailgate lamps are partitioned into three subsets – driver side, passenger side and
trailer tow connectors with the total vehicle load balanced between the driver and passenger side. The park lamp input
to the head lamp assemblies are a second signal to the LED array and functions much the same as the turn signal.
Aftermarket wiring must have provisions that:
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Maintain separation between all three subsets. The preferred method for aftermarket park lamps is to splice
into either the drivers or passenger’s park lamp circuits and use it to control a relay. The plow’s park lamp bulbs
will be driven by the relay’s contacts. (see schematic) The relay contact’s power source must be fused to battery
feed.
The aftermarket park lamps cannot be wired directly to the vehicle’s circuits as the electronic control module is
not capable of driving an incandescent bulb.
The following is an outline of the park lamp circuits:
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The front driver circuit is L77, 20 AWG WT/BR (pin 2)
The front passenger circuit is L78, 20AWG WT/OR (pin 2)
NOTE: The park lamp circuits driving LED arrays do not have bulb out diagnostics. The park lamp and turn signal uses the
same feedback circuit for detection of the LED array. When a failure occurs, the “LAMP OUT” telltale in the instrument
cluster will illuminate whenever the ignition is in the run position.
Day time running lamps (DRL) (Projector/Premium)
The DRL input to the head lamp assemblies are a third signal to the LED array and functions much the same as the
parking lamp signal. If DRL is required on the plow lights, splice into one of the DRL circuits and use that signal to control
a relay much like the park lamp circuit.
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The drivers DRL circuit is L58, 20 AWG WT/YL (pin 4)
The front passenger circuit is L59, 20AWG WT/DB (pin 4)
NOTE: The DRL circuits driving the LED arrays do not have bulb out diagnostics. The DRL also uses the same feedback
circuit for detection of the LED array. When a failure occurs, the “LAMP OUT” telltale in the instrument cluster will
illuminate whenever the ignition is in the run position.
Ignition Feed (Projector/Premium)
If an ignition feed is required, please see the “IGNITION FEED” section of the instruction set for the Quad/Base head
lamps.