Reversing sensors

sevenhills

My VW Crafter van had a new reversing sensor fitted last week, this morning I had a flat battery. Not sure if the two are connected.
The new sensor just shows a red light, as if its too close to a wall, but there is nothing behind. Not sure how these sensors work.

DUTR

last week? Then return to the fitters for it to be checked.

AdrianC

Does it have a towbar, or rear step? I'm wondering if that's triggering the sensor.

Certainly sounds like they've taken the feed from the wrong place - it should be from somewhere that's only live when you're in reverse.

DoaM

AdrianC wrote: »

it should be from somewhere that's only live when you're in reverse.

Or at least from somewhere that's only live when the ignition is on.

sevenhills

AdrianC wrote: »

Does it have a towbar, or rear step? I'm wondering if that's triggering the sensor.

Certainly sounds like they've taken the feed from the wrong place - it should be from somewhere that's only live when you're in reverse.

I dont know how they are wired up, but I havnt had a flat battery before. They just replaced the sensor at the back, all the other wires/parts were already in place.

AdrianC

sevenhills wrote: »

I dont know how they are wired up, but I havnt had a flat battery before. They just replaced the sensor at the back, all the other wires/parts were already in place.

Ah, my misunderstanding - I thought you meant they'd fitted an aftermarket sensor system to a vehicle that didn't previously have it at all.

sevenhills

DoaM wrote: »

Or at least from somewhere that's only live when the ignition is on.

Maybe I am barking up the wrong tree, blaming this sensor. Years ago all our vans had an isolator switch, which everthing was wired into.
We dont have one these days, so trying to find the cause of a flat battery, maybe just cold and the fact that the van is now five years old.