What should a van electrical system wiring diagram include?

A complete van wiring diagram should show: battery bank (with cell count and capacity), all charging sources (solar, DC-DC charger, shore power charger), fusing at each source, bus bars (positive and negative), all DC loads with wire gauges and fuse ratings, inverter connection and AC distribution, shunt for battery monitoring, and chassis ground points. Every wire should be labeled with gauge and color.

Where can I find a wiring diagram for my van electrical system?

Start with a diagram matched to your system size. Renogy and Victron both publish example wiring diagrams for their components. EXPLORIST.life and FarOutRide both publish detailed, open-source van wiring diagrams covering common configurations. Use these as a template and adapt to your specific component mix.

Van Electrical System Wiring Diagram (With Real Examples)

A wiring diagram before you buy or install anything saves hours of rework. Here's how to read one, what every section covers, and example configurations for common build sizes.

For the overall system concept: van electrical system beginners guide.

The key sections of any van wiring diagram

Charging sources (inputs)

Every diagram starts with the sources that put energy into the battery:

Solar panels → solar charge controller → battery
DC-DC charger → battery (fed from vehicle alternator via starter battery)
Shore power charger → battery (fed from 120V campground hookup)

Each source connects to the battery through appropriately sized wire and a fuse or breaker near the source.

Battery bank

The heart of the diagram. Shows:

Number and capacity of batteries (e.g., 2× 100Ah LiFePO4 in parallel = 200Ah)
How batteries are wired (parallel for same voltage, series-parallel for higher voltage)
Main fuse/breaker between battery and positive bus bar (sized for total system current)
Shunt on the negative side (for battery monitor accuracy)

Bus bars

Positive and negative bus bars distribute power to multiple loads and charging sources without running every wire directly to the battery terminals. All loads and chargers connect to the bus bars; the bus bars connect to the battery via the main fuse.

DC loads

Each DC load (12V fridge, fans, lighting, USB hubs, diesel heater) connects from the positive bus bar through its own fuse, then to the load, then returns to the negative bus bar. Wire gauge is sized for the load's current draw and run length.

Inverter

The inverter connects directly to the battery bank (not the bus bar) via very heavy cable (2/0–4/0 AWG) with a large fuse near the battery. Its AC output goes to an AC distribution panel or directly to 120V outlets.

Chassis ground

One or two chassis ground points tie the negative bus bar to the vehicle chassis, providing a common reference ground and completing the circuit via the vehicle body.

Example: 200Ah LiFePO4, 400W solar, DC-DC charger

[2× 100Ah LiFePO4 batteries in parallel]
         |
    [200A fuse]
         |
  [Positive bus bar] ──────────────────────────────────
         |                |              |              |
  [2000W inverter]  [DC-DC 30A]  [Fuse block]   [Solar ctrl]
  (2/0 AWG, 250A)   (14 AWG)      |                   |
                                   ├─ [12V fridge, 8A, 10A fuse]
                                   ├─ [Lighting, 5A, 10A fuse]
                                   └─ [USB hub, 3A, 5A fuse]

[Negative bus bar] ← shunt ← battery negative
         |
  [Chassis ground bolt]

Wire color conventions (US)

Color	Typical use
Red	Positive DC (12V)
Black	Negative DC return
Yellow	Switched positive (ignition-triggered)
Green	AC ground
White	AC neutral
Black/Red	AC hot