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DRL & Parking Lights

Control: Automatic with ignition

Power Source: PMU Out 23 (7A capacity, ~2.6A load)

DRL Auto-Off: PMU programming logic disables when CT4 SW3 activates headlights

Running Light Distribution

PMU Out 23 splices to all running/marker lights:

Destination Load Wire Notes
LP6 Headlight DRL (Pin 3) 0.8A 16 AWG Both lights
Maxbilt Round Trail Tail (RED) ~1A 16 AWG Both tail lights
RTL-S Running (Red) 0.8A Per RTL-S harness Chase light running function
Total ~2.6A PMU Out 23 capacity: 7A (37%)

Splice Location: Rear of vehicle (accessible for service)

PMU DRL Auto-Off Logic

Purpose: Automatically turns off DRL when headlights activate

PMU Configuration:

PMU Input 7 (In 7): CT4 SW3 headlight status signal
PMU Input 6 (In 6): Ignition RUN signal
PMU Output 23 (Out 23): DRL/Parking lights circuit

Programming Logic:
IF (In6_IgnitionRUN == ON) AND (In7_CT4_Headlights == OFF)
  THEN Out23_DRL = ON
ELSE
  Out23_DRL = OFF
END

Operation States

1. Ignition ON, Headlights OFF:

  • PMU In 6 = ON (ignition RUN)
  • PMU In 7 = OFF (CT4 SW3 not active)
  • PMU Out 23 = ON
  • Result: All DRL/parking lights illuminated

2. Ignition ON, Headlights ON:

  • PMU In 6 = ON (ignition RUN)
  • PMU In 7 = ON (CT4 SW3 active)
  • PMU Out 23 = OFF
  • Result: Headlights active, DRL off

3. Ignition OFF:

  • PMU In 6 = OFF
  • PMU Out 23 = OFF (regardless of headlight status)
  • Result: All DRL/parking lights off

Wiring

PMU Input Wiring:

  • In 6: Ignition switch RUN output (shared with CT4, SwitchPros)
  • In 7: CT4 SW3 output (tapped from headlight low beam circuit)

PMU Output Wiring:

  • Out 23: 16 AWG from PMU (engine bay) splits to:
  • LP6 Pin 3 (DRL): 16 AWG to each headlight (0.8A total)
  • Maxbilt Round Trail Tail RED wire: 16 AWG to each tail light (~1A total)

Wiring Method: Simple inline splice or parallel connection at PMU output. No junction box required for ~2A load.

Outstanding Items

  • Plan wire routing from ignition switch RUN to PMU In 6 (splits to CT4, SwitchPros)
  • Plan wire routing from CT4 SW3 to PMU In 7 (DRL cutoff logic)
  • Create PMU programming configuration with DRL auto-off logic