1.4.1 PMU Overview¶

Type: Programmable Power Management Unit with Data Logging
Model: ECUMaster PMU24 DL
Manufacturer: ECUMaster
Product Page: ECUMaster PMU24 DL
Installation Manual: PMU User Manual v101.1.5 (PDF)
Pinout Diagram: PMU-24 Pinout v1.1 (PDF)
Wiring Diagram: See Installation Manual (pinout diagrams for PMU24)
Specifications¶
Outputs:
- 24 programmable high-side outputs (10×25A, 6×15A, 8×7A)
- Total capacity: 170A continuous (power supply limited, not sum of outputs)
- Constraint: Only same-rated outputs can be combined (e.g., 25A + 25A ✓, 25A + 15A ✗)
- Out 17-24: Dual-purpose - configurable as 7A outputs OR 0-20V analog inputs
Key Features:
- Dedicated 12V switched input (Pin 7), up to 16 analog inputs, 9 digital inputs
- 256MB data logger (500 Hz), real-time clock, IMU, inertia switch
- 2× CAN 2.0 A/B (J1939 compatible), 24× tricolor LED indicators
- PC config via USB (USB to CAN adapter required)
Physical: 131×112×33mm, 385g, -40°C to +125°C operating range
Grounding Note: PMU is high-side switching only - it switches the positive wire to loads. Each load must have its own ground path back to the battery/chassis. The PMU's ground connection (14 AWG) is only for internal electronics reference, not load current return. This is why PMU doesn't require a heavy ground wire matching the 2/0 AWG power feed.
Configuration Software: PMU Setup v101.2.1 | Full Specs: PMU Manual
Capacity Analysis¶
| Outputs | Rating | Total | Used | Available |
|---|---|---|---|---|
| 1-10 | 25A each | 10 | 10 | 0 |
| 11-16 | 15A each | 6 | 6 | 0 |
| 17-24 | 7A each | 8 | 6 | 2 |
| Total | - | 24 | 23 | 1 |
Utilization: 23 of 24 outputs used (96%)
Primary loads: Radiator fan (OUT2+3+4: 3×25A combined), iBooster (OUT1+10: 2×25A non-adjacent), HVAC (OUT5: 25A), GMRS radio (OUT6: 25A), aux fans (OUT7+8: 2×15A), Dakota Digital (OUT9: 25A), wipers (OUT11: 15A), Ham radio (OUT12: 15A), CT4 (OUT13: 15A), DRL (OUT14: 15A), winch trigger (OUT15: 15A), Turbolamik TCU (OUT16: 15A), A/C clutch (OUT17: 7A), horn (OUT18: 7A), iBooster ignition (OUT19: 7A), intercom (OUT20: 7A), brake lights (OUT21: 7A), reverse lights (OUT22: 7A)
Load: ~253A theoretical peak (all radios transmitting + full radiator fan + iBooster braking), ~106A typical PMU circuits continuous (excluding radiator fan which varies 16-53A via PWM), total typical load ~140-170A (well within 300A PMU capacity)
Mounting: Engine bay, accessible for LED diagnostics and USB configuration
Related Documentation¶
- PMU Inputs - Input configuration and CAN bus integration
- PMU Outputs - 24-output configuration and load details
- PMU Programming - Logic examples and configuration
- START battery Distribution - PMU power source (2/0 AWG, 7 ft) and circuit breaker (250A)
- Wire Distance Reference - PMU to battery routing distance