I say ISO is so easy

First up, here’s a quick history lesson to understand some car audio jargon. You’ll often see ISO referred to when it comes to installing anything to do with car head-units. ISO is an acronym for "International Organization for Standardization". ISO or specifically ISO10487 to give it its full designation was created in 1995 and laid out the specification for an industry standard audio connector for connecting any aftermarket head-unit into a vehicle.Up until that point, car manufacturers and car audio manufacturers could, and would use their own unique wiring methods, colour codes and unique range of connectors which meant any upgrade to the factory audio usually involved hacking into the wiring of either the car or the head-unit. Older readers will recall setting out to install a new head-unit and the sheer joy of trying to decipher a rats nest of twisted wires, insulating tape and Scotchloks behind the dashboard.By creating an industry standard for all things audio, things suddenly got a whole lot easier and tidier for everyone.

An ISO connector consists of two eight pin connectors. They can be two separate connectors or sometimes they’re moulded into a single connector housing.

One set of eight pins handles the power side of things while the other eight pins provide the outputs to the front and rear speakers. An ISO connector will often fit straight into the back of an aftermarket head-unit.

Back of a head-unit that accepts ISO connections.

If the head-unit does not have an ISO socket in the back of it, the manufacturer will supply a short mini-harness or ISO adaptor to convert their own power socket into ISO connections.Typical mini-harness that converts a head-units connector into ISO

So now you know all about industry standard ISO connectors, you’ll be pleased to learn that Land Rover obviously ignored all of the above and did their own thing when it came to Defender factory audio installs…

However, don’t be too put off. By using the correct ISO adaptor for the age of your car, Defenders of any age are an easy vehicle to carry out any audio upgrade yourself.

Most pre-Puma (Tdci) vehicles will have already had their factory-fit head-units replaced so if you’re looking to replace a non-original head-unit then there’s every chance you may already have an ISO connector installed. Happy days!

There’s also every chance it’s had the wiring butchered to create the connections! We do sell a useful Universal ISO loom that allows you to tidy up any hack-job wiring and provide a pair of ISO connectors. The Universal ISO Loom has ISO connections on one end and bare wires on the other end.

200tdi & 300tdi Models

The earliest factory fit Defender radio-cassettes used a flat-pin connector on the head-unit. We sell an ISO adaptor to convert the flat-pin connector into ISO.

Td5 Models

Td5 models used both radio cassette and CD player that used a round pin connector.We can supply an ISO adaptor for Td5 Defenders to convert the Land Rover Round Pin connector into ISO connectors.

Tdci/Puma Defenders 

With the advent of the ‘Puma’ or Tdci in 2007 things suddenly get a bit more complicated. However, no need to worry - it’s easy when you know how.

Let’s start by splitting the Tdci into its two variants.  Early Tdci with the 2.4 engine and the later Tdci with the 2.2 engines with the changeover occurring in 2011/2012.

First generation Puma 2.4Tdci launched in 2007 were fitted with either a Land Rover branded CD player or an Alpine head-unit.Land Rover branded head-unit in the first Tdci modelsAll of these early cars use ISO connections for their audio which makes this generation of Defender stereo the easiest to upgrade since the factory ISO connections makes any aftermarket upgrade a simple plug & play exercise.ISO connectors found on pre <2012 DefendersWith the introduction of the 2.2Tdci engine in 2012, Land Rover in their wisdom stopped using ISO connections and swapped onto a large grey multiplug connector for the audio.

Factory Audio connector found in 2012> Defenders

By this time Land Rover were installing two different versions of Alpine head-unit at the factory.

The Alpine CDE130R was the base-level head-unit and didn’t have Bluetooth.The Alpine CDE133BT was the optional upgrade unit that had the addition of Bluetooth connectivity.Both units look very similar but the easiest way to differentiate them (aside from the model number on the front) is the square ‘Source’ button to the left of the main dial on the Bluetooth equipped CDE133BT.Both of these head-units are wired using a mini adaptor harness to connect between the small Alpine specific multiplug connector on the back of the head-unit and the large grey Land Rover audio connector in the dashboard.Back of a factory fit Alpine 130R head-unit showing non-ISO connection

The respective Alpine head-units use different connectors (pictured below) and are not interchangeable. The 130R used a small grey connector and the 133BT used a small black connector.When removing either of the factory Alpine units from 2012> models you will need to remove the factory adaptor harness and replace it with a 'Puma' ISO adaptor' to convert the LR grey 'Puma' connector into ISO.Puma ISO AdaptorA common mistake is getting an ISO adaptor and trying to connect directly into the factory Alpine connector. Remember that you’ll need to continue downstream of the small Alpine connector to find the additional connection at the large grey Land Rover plug within the dashboard and remove the factory mini harness from the car. 

Go Downstream of this small connector on 2012&gt; cars to find the large grey connector.

The ‘Puma’ ISO adaptor harness will now plug into the large grey plug within the dashboard to provide ISO connections.

If you have a 2011/12 model Defender, we would recommend removing the head-unit to check the head-unit wiring first and confirm whether you need an ISO adaptor or not. Changeover model years with Defenders are notorious for their mix of components and a using up of what’s left on the shelf!

Once again, if your Land Rover has already had its factory installed head-unit replaced with an aftermarket head-unit, then there’s a good chance someone will have already used an ISO adaptor harness.  The only 100% way to tell is to remove the head-unit and check. Useful tip. Land Rover only ever fitted Alpine units from the factory so if your dashboard has any other brand of head-unit in it, (e.g. Kenwood, Pioneer, Sony) then it’s safe to assume your car has already got ISO connections behind it.

A common enquiry we receive is from someone who has picked up a second-hand Land Rover Alpine head-unit from eBay or an Auto Jumble but can’t figure out how to wire it into their Defender because the socket on the head-unit doesn’t appear to match up with their car or any adaptor on our website.

As we referenced earlier, the 2012> factory fit Alpine head-units used a Land Rover specific harness to connect between Alpine's own small connector on the back of the head-unit and the large grey Land Rover audio connector. There isn't currently any aftermarket adaptor available for these units so if the head-unit didn't come supplied with its original adaptor harness (they typically don't!), then the only solution is to get hold of the Genuine Land Rover adaptor harness. Remember that the Land Rover harness will connect into the Alpine head-unit but the other end will only connect into the large Land Rover connector.

Genuine Land Rover Alpine Adaptor Mini-Harness use different coloured plugs at the head-unit end.

There are two part numbers for the Land Rover to Alpine adaptor harnesses:

LR040845 fits head-units WITHOUT Bluetooth (Grey connector)

LR040846 fits head-units WITH Bluetooth (Black connector).The cost of either harness from Land Rover is £75+ so unless the head-unit you’re buying is supplied with the correct adaptor harness then our advice would always be not to bother with second-hand Alpine units. The youngest factory fit Alpine head-unit is now 8-years old. Any new Alpine head-unit will come supplied with a proper ISO adaptor in the box making it far easier to install.

Leave a comment

All comments are moderated before being published

About us

It’s our own experience of owning, rebuilding, racing and travelling in Land Rovers all over the world that go into creating and handpicking the MUD range of products.

MUD seat rails were the very first MUD product we launched and from that single product offering packed on a kitchen table, MUD has grown into one of the most respected brands within the Land Rover aftermarket industry with users all over the world.  

Featured products

MUD Seat Rails
MUD MUD Seat Rails
In stock
MUD Snow CowlMUD Snow Cowl
MUD MUD Snow Cowl
From £26.67
In stock