An electric trailer-brake breakaway system is separate from the brake controller in the tow vehicle. If the trailer disconnects, its own charged 12V battery supplies power through a pull-pin switch to apply the trailer brakes. CURT offers several complete kits that differ by battery-case design, charge-test features and whether the charger is included.
Parts pictured in this guide
Select an image for product details, or jump to the parts list. Match the complete model and part number before ordering.
Choose the correct complete breakaway kit
| CURT part | Factory kit version | Charger | Case and identification |
|---|---|---|---|
| 52028 | Soft-Trac 2 | Included | Lockable battery box and one-bolt mounting arrangement |
| 52040 | Soft-Trac 1 with charger | Included | Lockable top-load case, switch, 12V 5Ah battery and hardware |
| 52041 | Soft-Trac 1 without charger | Not included | Lockable top-load case, switch, 12V 5Ah battery and hardware |
| 52042 | Push-to-Test, side-load | Included | Side-load case with battery-status indicator lights |
| 52044 | Push-to-Test, top-load | Included | Top-load case with battery-status indicator lights |
Identify the separately sold components
| Part number | Replacement part | What is included / what it replaces |
|---|---|---|
| 52023 | 12V sealed 5Ah breakaway battery | Battery only; match the original case terminals and space |
| 52025 | 12V breakaway battery charger | Charger only, for compatible CURT rechargeable breakaway systems |
| 52010 | Soft-Trac breakaway pull-pin switch | Switch and 48-inch cable; compatible CURT Soft-Trac models |
| 52020 | 48-inch replacement pull pin and cable | Replacement lanyard/pin for compatible CURT 52010 switch |
| 52022 | Lockable breakaway battery case | Case only; does not include a charger, battery or padlock |
| 52027 | Gasketed watertight battery case | Case only; does not include a charger or battery |
| Breakaway switch | Trailer tongue pull-pin switch | Separate lanyard attachment to tow vehicle; switch pivots as required |
| Battery charger | Trailer 12V charge circuit | Maintains breakaway battery without directly wiring the battery to tow vehicle charge supply |
| Electric brake output | Blue trailer brake conductor | Applies braking when the breakaway switch separates |
| Trailer battery negative | White ground conductor | The original factory drawing shows the trailer chassis ground |
Original manufacturer diagrams
The factory drawings identify the actual wiring or connections for the specified products, rather than a substitute diagram for a similar component.
CURT 52040 original breakaway charger, battery, switch and trailer wiring diagram
Before choosing or installing
CURT 52041 is the Soft-Trac 1 kit without a charger; 52040 includes the charger. Push-to-Test 52042 and 52044 differ in side-load versus top-load battery-case access. A new 52022 or 52027 case is not a complete system. Check the battery and switch before each towing trip, use a separate trailer-side breakaway battery, and never use the breakaway system as a parking brake. CURT's manual warns that the trailer connector should be disconnected from the tow vehicle before testing breakaway operation to avoid damaging the tow-vehicle brake controller.
Related towing and trailer-brake guides
See the matching products
Select a photo to view its corresponding NewRVParts product. Each manufacturer part number identifies a separate controller, assembly or replacement component.
52028 — CURT Soft-Trac 2 Breakaway Kit With ChargerComplete Soft-Trac 2 kit with charger
52040 — CURT Soft-Trac 1 Breakaway Kit With ChargerComplete Soft-Trac 1 kit including charger
52041 — CURT Soft-Trac 1 Breakaway Kit Without ChargerComplete switch, case and battery kit, but no charger
52042 — CURT Push-to-Test Side-Load Breakaway KitSide-load battery case with charge-test indicators
52044 — CURT Push-to-Test Top-Load Breakaway KitTop-load battery case with charge-test indicators
52023 — CURT 12V 5Ah Breakaway Replacement BatterySealed replacement battery, sold separately
52025 — CURT Soft-Trac 12V Breakaway Battery ChargerSeparate charger, not a complete breakaway system
52010 — CURT Soft-Trac Breakaway Switch With 48-inch CablePull-pin breakaway switch and lanyard