Battery cut off?

[discipleofsketch]

OK, i've been investigating more of the mystery wiring in my van, and while tracing a wire from the leisure battery, found this switch and relay behind the ignition switch:-



I didn't try the switch in case it sent me back in time or something, but a bit of googling around suggests it is a battery cut-off. Can anyone verify this - either remotely/ via crystal ball, or preferably because they have something the same and know what it does?

Are they just a safety feature, crude immobiliser or do they switch the stereo etc. over to use the leisure battery instead of the starter battery? (i'm hoping it's the latter as this is why I was following the wire in the first place, as I noticed my stereo runs from the main rather than leisure battery...).

[Jeff J]

Yes that's definitely a battery isolator switch & it looks like a split charge relay ,but without a circuit diagram I can't tell you what purpose they are serving. Mine is used both as a battery isolator, & because it is hidden, it adds a little to the security. It will not harm anything by turning it to the off position & you will find that you can then remove the key. That set up looks like it stops the leisure battery drawing current/being charged without the engine running & if that's the case it will not prevent the engine being started in the off position.

[discipleofsketch]

Yes that's definitely a battery isolator switch & it looks like a split charge relay ,but without a circuit diagram I can't tell you what purpose they are serving. Mine is used both as a battery isolator, & because it is hidden, it adds a little to the security. It will not harm anything by turning it to the off position & you will find that you can then remove the key. That set up looks like it stops the leisure battery drawing current/being charged without the engine running & if that's the case it will not prevent the engine being started in the off position.

Thanks Jeff - will try that tomorrow

[AdrianC]

Yes that's definitely a battery isolator switch

Whether it isolates the battery entirely, or just some ignition circuit as a cheap'n'cheerful immobiliser is another question, though - I'm guessing, given the location, the latter. A battery isolated would make far more sense right next to the battery, so you don't have a lot of live wiring un-isolated.

& it looks like a split charge relay

Looks like any ol' relay. <shrug>

Definitely have a poke around, but beware of shorting any lives that might be kicking around.

[California Dreamin]

What they said ^^^^^ however, using just one screw to mount it suggests that it might rotate when used and as it has wacking great live wires sticking out the back fireworks will shortly follow! TBH doesn't look very well done so be careful.

Martin

[Jeff J]

Yes that's definitely a battery isolator switch

Whether it isolates the battery entirely, or just some ignition circuit as a cheap'n'cheerful immobiliser is another question, though - I'm guessing, given the location, the latter. A battery isolated would make far more sense right next to the battery, so you don't have a lot of live wiring un-isolated.

& it looks like a split charge relay

Looks like any ol' relay. <shrug>

Definitely have a poke around, but beware of shorting any lives that might be kicking around.

He said he was tracing wires from the leisure battery so I thought it was a fair guess that someone had wired it up to act as a split charge relay. I did qualify it by saying without a cct. diag. it was speculation

[discipleofsketch]

Ok, the results are in: I think it's a crude immobiliser, ignition doesn't work when it's off, but stereo/ front 12 volt socket do (which are permanently wired into the starter, rather than leisure battery).

I'm actually having an insurance-approved immobiliser fitted, so at least I can warn the guy that there's something already in there to confuse things!