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Command Touch CT4

Model: SwitchPros Command-Touch CT4

Manual: https://www.switchpros.com/wp-content/uploads/CT4-Rev-1.0.pdf

Type: Programmable steering column-mounted turn signal and accessory controller

Function: Turn signals (left/right), headlight control, and auxiliary accessories

Power Source: PMU Out 13 (15A, programmed CONSTANT for hazards when ignition off)

Mounting Location: Steering column

Ground: Chassis ground (via ignition/ground harness)

IP Rating: IP67

GPS Module: Included (enables automatic turn signal cancellation based on speed and steering angle)

Overview

Additional Features:

  • Built-in Hazard Switch: Flashes all outputs in sync when pressed
  • Built-in Audio Module: Audible sound when turn signal is active
  • Lane Change Feature: Lever press <0.5 sec flashes turn signal 3 times

Turn Signal and Lighting System Integration

Turn Signals

  • Front Turn Signals: Amber LED turn signal lights (dedicated turn signal only)
  • Wired to CT4 SW1 (right) and SW2 (left) outputs
  • Wire gauge: 14 AWG from CT4 to junction, 16 AWG to each light

  • Note: These are dedicated turn signals, not dual-function with parking lights

  • Rear Turn Signals: Maxbilt Trail Tail lights (integrated brake/turn/marker/reverse)

  • Brake/Turn wire (Yellow): Combined brake and turn signal function
  • Wired to CT4 SW1 (right) and SW2 (left) outputs (parallel with front signals)
  • Wire gauge: 14 AWG from CT4 to rear junction

Headlight Control

  • Headlights (SW3 - PULL): Baja Designs LP6 headlights (low beam)
  • Pull lever → Activates headlights (low beam)
  • Power: PMU Out 13 (CONSTANT) → CT4 internal switching → SW3 output
  • CT4 SW3 output → LP6 Pin 1 (low beam, both lights in parallel)
  • CT4 handles switching internally (10A output capacity, 3.6A actual load)
  • Disabled when ignition off (via ignition signal from ignition switch RUN)
  • Latching on/off control (pull once to turn on, pull again to turn off)
  • Wire gauge: 14 AWG from CT4 SW3 output to LP6 headlights

  • When active: Also triggers DRL cutoff relay to disable DRL circuit (SW3 output tapped to relay coil)

  • High Beams (SW4 - PUSH): Switches to high beams

  • Push lever (while headlights on) → Activates high beams
  • Power: PMU Out 13 (CONSTANT) → CT4 internal switching → SW4 output
  • CT4 SW4 output → LP6 Pin 4 (high beam, both lights in parallel)
  • CT4 handles switching internally (10A output capacity, 5.6A actual load)
  • Disabled when ignition off (via ignition signal from ignition switch RUN)
  • CT4 provides mutual exclusivity (high beam disables low beam automatically)
  • Momentary or latching toggle (programmable)
  • Wire gauge: 14 AWG from CT4 SW4 output to LP6 headlights

DRL/Parking Lights

Automatic ignition-controlled circuit that powers:

  • License plate lights
  • LP6 Headlight DRL function (Pin 3) - via cutoff relay
  • Front 2" LED side markers (parking function)
  • Maxbilt tail light RED wire (marker/parking function)

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

DRL Auto-Off: PMU programming logic disables when CT4 SW3 activates (headlights on = DRL off)

Wire gauge: 14 AWG from PMU to junction, 16 AWG to each light

See PMU DRL Auto-Off Logic section below for complete wiring.

Wiring Pinout

12-pin Connector on CT4:

Wire Color Label Function Connection Point Notes
Brown SW1, UP Right Turn (CT4 output) Front/rear right turn signals 10A max per output
Red SW2, DOWN Left Turn (CT4 output) Front/rear left turn signals 10A max per output
Orange SW3, PULL Headlights (low beam) LP6 Pin 1 (low beam, both lights) + DRL cutoff relay coil 10A output, 3.6A load, disabled when ignition off
Yellow SW4, PUSH High Beams LP6 Pin 4 (high beam, both lights) 10A output, 5.6A load, disabled when ignition off
Red (thick) 12V Supply Main power input PMU Out 13 (15A CONSTANT) Powers all SW outputs, allows hazards when ignition off
Black Ground Ground return Chassis ground or firewall ground stud Via ignition/ground harness
White/Gray Ignition Ignition signal input Cabin ignition bus bar Terminal 1 (18 AWG, ~20 mA, fused per bus doc) Disables SW3/SW4 when ignition off, keeps SW1/SW2 active

Programming Configuration

Recommended configuration for this build:

  1. Turn Signal Mode: GPS turn signal mode (automatic cancellation based on speed and steering angle)

  2. Ignition Control: Ignition-aware mode (SW1/SW2 always active; SW3/SW4 disabled when ignition off)

  3. ON-OFF/Momentary:

  4. SW1/SW2: ON-OFF (latching turn signals with GPS auto-cancel)
  5. SW3 (Headlights): ON-OFF latching (pull to turn on/off)

  6. SW4 (High Beams): Momentary or ON-OFF (choose preferred behavior)

  7. Low Voltage Disconnect: Enabled for all switches (protects battery from over-discharge)

  8. Flash/Strobe: Disabled (turn signals use built-in flash pattern)

  9. Switch Memory: Disabled (turn signals don't remember state after ignition cycle)

GPS Module Configuration

  • Manual Override: Can still manually cancel by moving lever to center or opposite direction
  • Mounting: GPS antenna must have clear view of sky (mount on dash or near windshield)
  • Calibration: May require initial calibration drive for optimal performance

PMU DRL Auto-Off Logic

Purpose: Automatically turns off DRL when headlights are activated via CT4 SW3

Implementation: PMU programming logic (no external relay needed)

PMU Configuration:

PMU Input 7 (In 7): CT4 SW3 headlight status signal (tapped from low beam circuit)
PMU Pin 7: Ignition RUN signal (12V switched input)
PMU Output 23 (Out 23): DRL/Parking lights circuit

Programming Logic:
IF (Pin7_IgnitionRUN == ON) AND (In7_CT4_Headlights == OFF)
  THEN Out23_DRL = ON
ELSE
  Out23_DRL = OFF
END

Installation Notes:

  • Tap CT4 SW3 output (low beam circuit) to PMU In 7 for headlight status monitoring
  • Run wire from PMU Out 23 to DRL junction
  • Total DRL/parking circuit load: ~2.6A — see DRL & Parking for the itemized load breakdown and wiring
  • PMU Out 23 capacity: 7A (sufficient for the ~2.6A load)

Installation Checklist

Check-off items only. Wire gauges, pin assignments, and tail-light color codes live in the Wiring section above and the linked light pages. Controller power feed (PMU Out 13) and ignition-signal distribution are tracked in the Power Systems Checklist.

Power, Ground & Ignition

  • Confirm CT4 12V supply (PMU Out 13) landed at steering column
  • Confirm CT4 ground connected
  • Confirm CT4 ignition signal connected (cabin ignition bus bar Terminal 1)
  • Verify SW3/SW4 (headlights) disabled when ignition off
  • Verify SW1/SW2 (turn signals/hazards) work with ignition off (safety feature)

Lighting Wiring

  • Confirm CT4 SW1 (right turn) → front right marker + rear right tail light
  • Confirm CT4 SW2 (left turn) → front left marker + rear left tail light
  • Confirm Maxbilt tail lights wired per page wiring table
  • Confirm CT4 SW3 → LP6 low beam (both lights)
  • Confirm CT4 SW4 → LP6 high beam (both lights)
  • Confirm CT4 SW3 tapped to DRL cutoff relay coil
  • Confirm CT4 SW3 tapped to PMU In 7 (headlight status)
  • Confirm PMU Out 23 → DRL/parking junction (license plate, LP6 DRL, markers, tail markers)

GPS Module

  • Determine GPS antenna mounting location (clear sky view)
  • Confirm GPS antenna connected to CT4 GPS input
  • Perform GPS calibration drive per CT4 manual

Programming

  • Program all switches to battery control mode
  • Program GPS turn signal mode (auto-cancel)
  • Program SW3 (Headlights) to ON-OFF latching
  • Program SW4 (High Beams) to preferred behavior
  • Enable low voltage disconnect for all switches
  • Disable flash/strobe and switch memory

Testing

  • Verify turn signals flash front and rear in sync, at correct rate
  • Verify hazards work with ignition off
  • Verify lane-change mode (short press = 3 flashes, auto-cancel)
  • Verify GPS auto-cancel and manual cancel
  • Verify headlight control (SW3 low beam, SW4 high beam mutual exclusivity)
  • Verify DRL auto-off when headlights active, back on when off
  • Verify brake lights work independently of turn signals

Outstanding Items

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