Fitting aftermarket HU and the vagaries of Harmon Karmon

I have tried to look at all the threads about fitting aftermarket HU when you have the HK Amp etc, and honestly I'm a bit lost. I have the 2004 Freelander TD4 HSE with HK Amp under the seat and the 2DIN factory HU. I want to install this unit, Kenwood KMM-BT502DAB. I have the 2DIN/1DIN mount.

Where I need the help is;
1. Some posts say bypass the HK amp, others say use it, but I don't understand that logic as it has 9 speakers, 9 sets of wires and presumably it sends the right frequencies to the small speakers, to the door speakers, and to the boot speaker? I don't see how the new HU would know what type of speaker was on the end of the wires?
2. If I keep the amp in line, what connectors do I need to buy?
3. If I bypass the amp, does that change the connectors needed?
2. Halford's will sell me a wiring harness for £35 and another for £12 for the steering controls. The advantage of using them is they looked up my Reg and it tells them what to order in. I am sure I can get them cheaper on the internet, but how do I know what to buy?
Many thanks in advance for your help

Bockhamptoner said:

Some posts say bypass the HK amp, others say use it, but I don't understand that logic as it has 9 speakers, 9 sets of wires and presumably it sends the right frequencies to the small speakers, to the door speakers, and to the boot speaker? I don't see how the new HU would know what type of speaker was on the end of the wires?

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You can keep the HK amp or replace is with a more standard amp. There are 6 separate speaker wires, which supply all 10 speakers with the necessary frequencies.

Keep in mind that doing away with the HK amplifier, will also do away with the electronic sound processing that the HK amplifier applies to the sound before driving the speakers.

Bockhamptoner said:

2. If I keep the amp in line, what connectors do I need to buy?

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I'm sure I've seen them somewhere, or you could make up your own?

Bockhamptoner said:

3. If I bypass the amp, does that change the connectors needed?

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Yes and the sound produced too.

Bockhamptoner said:

2. Halford's will sell me a wiring harness for £35 and another for £12 for the steering controls.

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Does that keep the HK amp or not? The wheel controls are normally easy on modern HUs.

Hi I'm in exactly the same situation as the original poster. I would love to get an android double DD head unit but don't feel confident in the wiring harnesses or adapter frames. Is it really as simple as it sounds? I will be watching the thread with great interest

Here's the wiring diagram for both types of audio system including the HK amplifier.
View attachment 119595 View attachment 119596

My personal preference is to keep the amp, don't need the agro of patching the wires to isolate the amp.
The spec of new HU says "Molex to ISO" output, which means nothing to me... but it looks like this...

so does anyone know what connector I need to patch this the connector to the plug from existing HU down to the amp?
And what I need to buy for the steering wheel?

Thanks for wiring diagram, I had that saved from another post but want to avoid fiddling with anything, would just like to buy a connector from new HU to existing connector, and add the steering control? Min fuss is the aim

Nodge68 said:

Here's the wiring diagram for both types of audio system including the HK amplifier.
View attachment 119595 View attachment 119596

Click to expand...

That's very handy thank you Sir!

Bockhamptoner said:

so does anyone know what connector I need to patch this the connector to the plug from existing HU down to the amp?

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That HU has a standard DIN plug, so there's probably something readymade for it. I'll have a look when I get a moment.

Edit: Thinking about it. If it had the Becker nav unit in there, then those use standard DIN plugs anyway, so have you tried plugging it straight in to see what happens?

Bockhamptoner said:

And what I need to buy for the steering wheel?

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It looks like the wheel controls are on the standard headphone type plug. But you need to see if the HU has programmable button recognition, as many modern HUs do. If not you'll need an adapter to convert the resistance values of the factory switches.

Need to connect the amp trigger feed from the new head unit to the purple/yellow wire on the vehicle harness and that will activate the amp

The existing HU isn't Becker Nav, it's the 6 CD unit at top, radio in middle and preset buttons below type.

Bockhamptoner said:

The existing HU isn't Becker Nav, it's the 6 CD unit at top, radio in middle and preset buttons below type.

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That's the Vestion HU. There's a converter from that to standard DIN, as I used one when I fitted my Sony HU.
I converted my wheel controls to work with my Sony HU.

Thank you, do you have a link to the converter? And details how you got the steering controls to work please

Sorry to ask more questions and appreciate the help
The HU has these things;
Pre-out 1 RCA
Pre-out Output Level 2.5V
Power Control (P.CON) wire
2-way (Tel/Navi) mute wire
Preout Rear / Subwoofer Switchable
Hopefully one of those is the feed to turn on the Amp, if so, if I have the correct loom converter will it turn the amp on, or will I have to find the amp trigger feed mentioned by td4van above?
How will I know the converter loom and steering wheel connects?

This may well be the last question if someone knows the answer
I found Autoleads mentioned in many posts, put my Reg in and it gives me these choices, but do I need one, some or all of these to patch my new HU ISO to the existing loom plug that goers down to the HK amp?

Harness adapter;
https://catalog.autoleads.co.uk/cat...t-and-audio-fitting-harness-adaptors/pc2-80-4

Something for Landrover vevicles with resitive steering controls;
https://catalog.autoleads.co.uk/catalog/steering-wheel-control-adaptors-cp2/cp2-fd24

And another resitive steering wheel control;
https://catalog.autoleads.co.uk/catalog/steering-wheel-control-adaptors-pc99/pc99-x91

And a SOT lead, whatever that is.... I am hoping it's and all in one fix as it has a lot more plugs and wires than the others
https://catalog.autoleads.co.uk/cat...lutions-accessory-interface-leads-sot/sot-085

They are very helpful, email them with your details and they will tell you exactly what you need.

thanks

You need the P Con wire to trigger the amp and it’s unlikely the adaptor will include the wiring for that so you’ll have to manually connect the two wires

Hi Nodge68 - could you tell me where the wiring diagram came from please, when i try to print it out the text is fuzzy
View attachment 119595View attachment 119596

Have the radio, Autoleads were helpful, all the bits came, just got to figure out what goes where now

I am a bit confused by the wording in the PC99 instructions.
It says ...
connect new stereo to pc99 harness and connect the patch lead to the pc99 module, do not connect patch lead to the stereo at this stage. (Q. which is the patch lead?)
connect the loom to vehicles connector and locate any other connections required.
Once all connections made, turn on ignition, power up stereo.
manually tune a strong station and save.
turn off
whilst unit is off, connect the patch lead to the connector on the rear of stereo (Q. does it mean to the cables and plugs (ISO), or actually to stereo? and again, which is the patch lead?)
Sorry I am being dense but the instructions are clear the steering unit won't work if this isn't done in correct order

Bockhamptoner said:

Hi Nodge68 - could you tell me where the wiring diagram came from please, when i try to print it out the text is fuzzy

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It's a screenshot of the LR wiring diagram. I don't have a higher resolution picture, I don't think.

The manual is available to download from this site somewhere.