Load
See the Jabsco PARMAX HD4 Q401J-115S-3A connection points and wiring example. Open the diagram in Crimp to add your equipment and plan the cables between them.
Open this example as a new project. Use your own parts and cable lengths to make the plan yours.
Use the diagram as a starting point for your installation. Replace the example equipment and cable lengths with your own, and check the connections against your exact model's instructions.
10 ft one way
12 V system
Sized against ABYC E-11. The design current is the part's continuous draw. The length is one way; voltage drop includes an equal-length return.
The editable example uses 3.048 m (10 ft) runs unless a shorter run is stated. Metric overviews round these to 3 m. Adapt the parts and lengths to your installation before choosing cable and protection.
The Q401J-115S-3A example uses the specified 15 A fuse and 10 A maximum running current. Verify actual cable length, pressure-switch operation and plumbing. The fuse does not establish motor startup current. Manufacturer installation manual
Wiring diagram
Open this example in Crimp to use your own parts and cable lengths. Review the assumptions and installation notes as you adapt the circuit.
The Q401J-115S-3A example uses the specified 15 A fuse and 10 A maximum running current. Verify actual cable length, pressure-switch operation and plumbing. The fuse does not establish motor startup current. Manufacturer installation manual
Edit this wiring exampleInstallation notes
Guidance for this model, with sources linked beside the relevant advice.
Verified against the manufacturer's documentation (rev. Q401J-115S-3A Rev B, 12/2025; HD IOM 81000475 Rev C, 07/2021), checked 2026-10-01. Manufacturer documentation →
Q401J-115S-3A is the 12 V PARMAX HD4 freshwater pump: 4 GPM open flow and 40 PSI shut-off. It starts as an open tap lowers system pressure and stops after the taps close and pressure recovers. Its flow at an open outlet is not a promise of 4 GPM through a restrictive shower head. This exact suffix matters; other HD and HotShot models have different pressure and electrical ratings.
Use a dedicated switched positive feed to the red lead and a negative return to the black lead. Fit the specified 15 A fuse and retain access to the pump isolator. The exact datasheet gives a maximum operating point of 10 A at 40 PSI, which is the catalog's sizing draw. The fuse is protection, not operating consumption; no starting surge has been invented.
The pump's short factory leads are 14 AWG. They do not establish the required size for an arbitrarily long boat run. Select extensions for ampacity and voltage drop over the complete circuit, using the HD installation manual's length table. Published operation is 9–13.6 V. A battery voltage reading alone does not show what reaches the pump while it runs. The terminal limit is a protection-based planning bound.
Fit the required strainer before the inlet, keep suction joints airtight, and use the correct quick-connect fittings with their retaining clips fully engaged. Leave space to withdraw those clips and clean the strainer. Arrange mounting and hose support so vibration is not carried into rigid plumbing. The exact datasheet permits self-priming up to 2.4 m, but a short, unrestricted suction route gives more margin.
An accumulator can smooth small intermittent demands and reduce rapid cycling; it is not a substitute for finding a leak. The pump has thermal protection and is intended for intermittent duty. Its ability to tolerate dry operation does not make an empty tank a useful normal operating condition.
Fill the tank, open the outlets and let trapped air clear, then close them and confirm the pump stops at pressure. Inspect every joint under pressure. If it cycles with all taps closed, check leaks, a dripping tap and the check-valve path. If it runs without useful flow, inspect the inlet strainer and suction-side air leaks before changing the pressure switch. A hot motor that stops and later restarts may be reaching thermal protection; investigate restriction and excessive duty rather than bypassing it.
Exact HD4 datasheet, pp. 2–3, establishes the suffix-specific ratings and required strainer. PARMAX/HotShot HD installation manual covers installation, wiring tables, priming and maintenance. Both downloads are indexed in the marine evidence ledger.
Build it out
Add Q401J-115S-3A to your diagram, then connect your batteries, chargers and loads. Crimp calculates cable sizes and checks the connections as you draw.
Every cable you draw there is sized against ABYC E-11, from the same tables as the reference on this page.
Technical reference
Check the model, ratings and connection points against your own unit before choosing installation hardware.
Check stud sizes, fuse type, run length and how warm the space gets against the gear you actually have before you order.
Catalog connection points, current direction and planning limits. Check the manufacturer's pinout and connector ratings before installation.
+
pos
positive · input
−
neg
negative · input
Method & provenance
Manufacturer specifications describe the equipment. Crimp calculates cable results from the circuit and assumptions you enter.
From the maker
Manufacturer, model, ratings and which terminal does what come from the catalog. A newer revision, or the nameplate on the unit in your hand, can say something different — when it does, the nameplate wins.
ABYC E-11
Sized against ABYC E-11 — the US reference, and what Transport Canada accepts as an alternative to TP 1332 for pleasure craft under 24 m. The run length and the current above are what drive the result. Crimp doesn't know how warm your space gets; draw the cable inside an engine-bay zone on the canvas and it sizes for the heat.
Next step
Open this example as a new project. Add your equipment and cable lengths, then review the sizing and checks for your setup.