Tail, Brake & Reverse Lights¶

Type: LED Tail Light (4-function: Brake, Turn, Marker, Reverse)
Model: Round Trail Tail
Manufacturer: Maxbilt
Product Page: Maxbilt Round LED Tail Lights
Quantity: 2
Mounting: Rear quarter panels
Power Source: CT4 (turn), PMU Out 21 (brake), PMU Out 22 (reverse), PMU Out 23 (marker)
Wire Functions¶
| Color | Function | Connection | Wire Gauge | Notes |
|---|---|---|---|---|
| BLACK | Ground | Chassis ground | 16 AWG | Clean metal-to-metal |
| WHITE | Reverse | Reverse splice | 16 AWG | Parallel with Squadron Sport reverse |
| YELLOW | Brake/Turn | Turn splice + Brake splice | 16 AWG | Combined function, internal diodes |
| RED | Marker/Parking | Running splice | 16 AWG | DRL/parking circuit |
Reverse Lights¶
Power: PMU Out 22 (~5A load, 16 AWG) Trigger: Transmission reverse switch → PMU In 3 Circuits: Maxbilt WHITE + Squadron Sport reverse + WolfBox camera trigger (parallel)
Wiring:
- Transmission reverse signal → PMU In 3
- PMU Out 22 → Maxbilt WHITE + Squadron Sport reverse lights + WolfBox trigger (parallel)
- Chassis ground
Load Breakdown:
- Maxbilt WHITE: ~2A (LED, 130 red + 18 white LEDs total)
- Squadron Sport pair (557805): 2.8A (1.4A × 2)
- WolfBox trigger: negligible
- Total: ~5A (PMU Out 22 capacity: 7A, 71% utilization)
Brake Lights¶
Power: PMU Out 21 (7A capacity) Trigger: Brake pedal switch → PMU In 2
Brake Light Distribution¶
PMU Out 21 splices to all brake lights:
| Destination | Load | Wire | Notes |
|---|---|---|---|
| Maxbilt Round Trail Tail (YELLOW) | ~3A | 16 AWG | Both tail lights |
| RTL-S Brake (Yellow) | 1.45A | Per RTL-S harness | Chase light brake function |
| Total | ~4.5A | PMU Out 21 capacity: 7A (64%) |
Splice Location: Rear of vehicle (accessible for service)
Brake/Turn Signal Integration¶
Maxbilt Round Trail Tail lights have internal diode isolation for combined brake/turn function. No external diodes required.
Operation:
- Right turn active → right tail light flashes
- Brake pressed → both tail lights solid
- Right turn + brake → right flashes, left stays solid
Marker/Parking Lights¶
Power: PMU Out 23 (DRL/parking circuit) Maxbilt Connection: RED wire Control: Automatic with ignition Shared Circuit: LP6 DRL
See DRL/Parking Lights for circuit details.
Outstanding Items¶
- Plan wire routing from CT4 to rear tail lights
- Plan wire routing from PMU Out 21/22 to rear tail lights
Related Documentation¶
- PMU Power Distribution - PMU Out 21, Out 22 circuits
- Command Touch CT4 - Turn signal control
- DRL/Parking Lights - Marker/parking circuit (RED wire)
- Communication & Camera - WolfBox camera reverse trigger