Renault Master Battery Isolator

LA&Murph

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Alright you lovely lot, since it is 1st December, I am offering up hot chocolate with all the trimmings and some cookies of your choosing to anyone that can help! I have a 3.5t horsebox (The Renault/Vauxhall one, so any owners of this vehicle type can help!) and my insurance requires that I have a battery isolator - not a bad idea in itself, I was planning on one anyway. The internet has not been much help, so I am asking for yours :).

What sort of isolator do you have fitted to yours? Is it a switch in the cab somewhere? One fitted to the battery itself with a key that can be removed to cut power? However, presumably not on the battery under the cab, I don’t fancy unscrewing the battery compartment every time I go out!

I had bought one but it wouldn’t fit anywhere so it’s been sent back. Pics would help, or a link to any that fit would do me just nicely too!
 
How old is it .does it have central locking.?

If after jan 1998 it will have a factory fitted cat II imobiliser fitted so it wont need an isolator. If it fits into this time frame
point it out to the insurance company they should not ask for more and to be honest a battery isolator will be inferior as a security system. Fitting a battery isolator will interfer with this system anyhow
 
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Yep, there is ALWAYS information that I miss out. Extra cookies for you!
It's a 2006 with an alarm and immobilizer as standard. It was in the event of a fire, I wouldn't be covered for insurance should it burst into flames!
I thought it may be worth the risk not getting one because it's not often that a vehicle catches fire when not in use, and almost as rare whilst in use (when the isolator would be disabled anyway).
 
I have an old (2000) Renault box, and my battery isolator is fitted directly onto one of the battery terminals (a plastic screw type thing). I have to lift up the hood and screw it down to make contact (i.e. engage the battery). I use it mostly to make sure my battery doesn't drain while the box is parked. I guess it would take someone breaking into the cab to pull the latch, or forcing up the hood to be able to access it. Not sure if that makes it in any way a useful safety device against theft. It should be dead easy to have one of those fitted (my battery is very easy to access once the hood is lifted), though mine came with the box, so wouldn't know how to do it myself.
Only annoying side effect is that everything else battery operated is reset/doesn't work when you isolate the battery. I.e. alarm system is off, clock and programmed radio stations are reset.
 
I fitted the isolator switch to the panel that covers the battery. Just required a suitable sized hole cutting to fit the isolator through from the bottom of the cover plate and a longer lead for one side of the battery to allow the cover to be lifted enough to disconnect the battery.
Has worked for 4 years now without any issue and my initial slight concern of key being caught with a foot has proved unfounded.
 
supsup, I had one with the plastic screw, but it was too big to either connect to the battery directly, or fit to the terminals under the bonnet (stupid pipes and stuffs in the way!). Sounds like yours was designed with a bit more access in there.

PaddyMonty, that sounds feasible. We're going to be rummaging around in the cab to fit the reversing camera anyway, so what's a little bit more when the tools are already out! Also, ashamed I didn't think of that.
 
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I really dont see the point as it will disable all the electrics including the alarm sort of defeating the object of having one ,Before you do it make sure you have the radio code as that will need re doing every time .. They are very easy to bypass anyhow so no good as a security measure. I think the fire one is a bit of a joke on their part
 
I have recently had a horsebox fire, the Isolator was in use at the time and it was the power from my leisure battery that started the fire.
Thankfully it was noticed very quickly and leisure battery disconnected fast! fire was doused and only minimal damage was done (couple of areas of scorched carpet and some burnt wires) but I have since had the whole lorry rewired!
 
I have recently had a horsebox fire, the Isolator was in use at the time and it was the power from my leisure battery that started the fire.
Thankfully it was noticed very quickly and leisure battery disconnected fast! fire was doused and only minimal damage was done (couple of areas of scorched carpet and some burnt wires) but I have since had the whole lorry rewired!

OP are you maybe assuming the wrong battery for the isolator as it is indeed usually a requirement to have an isolator on the leisure battery system! Which makes more sense I would request clarification from them. This post suddenly made it clearer to me.
 
OP are you maybe assuming the wrong battery for the isolator as it is indeed usually a requirement to have an isolator on the leisure battery system! Which makes more sense I would request clarification from them. This post suddenly made it clearer to me.

My isolator disconects the main lorry battery so that my leisure battery and my tachograph do not draw power from it whilst the lorry is parked up.
I'm not sure a 3.5ton lorry would have a leisure battery as normaly thye dont have a living.
 
I used to have a 2001 Renault master. It had a battery isolator fitted, the type with a big red key. The key was fitted behind the glove compartment. I used it mainly so that I didn't have a flat battery every time I went to use it. It worked fine. The company that converted it fitted the isolator switch as part of the conversion process.
 
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