Product details
Towbar 12V 7-way universal bypass relay wiring kit
This UmbraRimorchi TEB7AS 12V 7-way bypass relay kit takes a lot of the faff out of towing and keeps things reliably simple. It’s aimed at modern cars with multiplex or CAN-bus wiring and bulb-failure systems that don’t much like extra trailer loads. Rather than trying to piggyback the car’s lighting circuits, this kit draws a clean feed from the battery to power the trailer lights – straightforward, sensible and much less likely to upset the vehicle’s electronics.
What’s in the box
- Smart 7-way bypass relay with audible indicator
- Live feed cable to run down the vehicle
- Waterproof fuse holder and fuse
- Battery eye connector and crimp connector
- Full printed fitting instructions
Why this kit helps
If your car flags a bulb failure when a trailer’s hooked up, or the on-board electrics are overly sensitive, this bypass relay sorts it by taking the trailer lighting power straight from the battery. The benefits are no false bulb warnings, steady lighting for your caravan or trailer, and an audible beep so you can hear the indicators are working when you’re towing — handy on a dark A-road or when reversing at night.
Technical details and compatibility
Manufacturer: UmbraRimorchi. Part number: RelaySP. Receiver size reference in fitter notes: 50 mm. Designed for 12V systems and modern cars with multiplex/CAN-bus wiring and bulb-failure monitoring. Not suitable for vehicles that require a negative feed setup. Special features include a waterproof fuse holder, heat-resistant components and a compact, lightweight relay unit.
Installation notes and common questions
- Fitting instructions are included, but if you’re unsure about a vehicle’s wiring, check with a fitter or supply the vehicle details so compatibility can be confirmed.
- The kit needs a good, clean battery connection — make sure the terminals are in decent nick before fitting.
- The audible relay will not beep if a trailer bulb is actually blown — that’s deliberate so genuine faults remain obvious.
- Not suitable for negative feed systems — if your vehicle’s wiring uses a negative feed arrangement, this kit won’t work.
In short, it’s a tidy little upgrade for anyone with a modern car who wants dependable 7-way trailer electrics without upsetting the vehicle’s electronics. No more guessing whether the trailer lights are being fed properly — just a sensible battery-fed solution with all the bits included, so no last-minute dash to the motor factors. If you’re in any doubt about fitment, check your vehicle details or ask for a quick compatibility check before buying.