Fitting aftermarket HU and the vagaries of Harmon Karmon

OMG I feel like I'm being a pain, but I bought the PC99 adaptor as Autolead said, and I I think I've followed the instructions, see questions above. However, it's in, but....
The Left/right balance works. But the Fader doesn't.... and the the steering controls don't work.
This confused me because the PC99 has three plugs attached.
One goes to the big oblong connector that feeds speaker channels to the amp. I have wired in the power feed to the amp, so it works and I get sound.
But PC99 has two other leads with plugs a perfect fit to the PC99 steering control box. As far as I can see the two wires in position 18 and 19 holes on the car's adaptor feed directly into the the steering control, so naively I expected it to work with no jiggery pockery needed... but it didn't.
So I am down rear speakers and pos sub woofer, and down the steering controls... any ideas?
I am happy to patch the amp connector to just route the new HU directly to speakers... but the Kenwood KMM-BT502DAB appears to have some phono connections that imply they are for sub-woofer?
Any help gratefully accepted

This is what the loom/connectors etc look like
https://photos.app.goo.gl/w8mDU1ETHRNNnFMg6

It's and I have some sound but it's not right and steering controls don't work. Please be patient with the newbie
For now I have not bypassed the amp, used the work from the ISO to power it up.
But the Fader doesn't work, only R and L. HU has two settings 2-way or 3-way X over, neither help.
I think I need to bypass the amp using the image like this attached (although I can't figure out why it doesn't have 9 pairs of wired for 9 speakers?)
I'm also worried by the steering controls, because the PC99 came with two extra connectors that fit the PC99 box, and bot wires trace back to wires in position 18 and 19 on the car loom plug that used to feed into the original HU, on the Audio wiring imaged shared to me earlier, they are called Analogue remote 1 and 2, which I had assumed was from the steering wheel controls. If I should have patched something, can someone tell me which of the original looms wires come from the steering wheel?
Thanks,

Now I feel stupid and cross with Autoleads. I called their helpline and bought what they told me and what they didn't say is that I needed the steering wheel patch lead for my Freelander... anyway, it's ordered.
BUT I still have the headache that my Kenwood KMM-BT502DAB has a L - R Rear/Sub Woofer out put.
I am looking for a way to take the KH amp out, so see previous image for the way to patch it.
BUT that just leaves the question of when amp is out of picture, what cables I run from the L-R outputs, down to the amp old connector and into the sub-woof in the boot?

In the settings menu on the headunit you can turn on/off the output for the rear speakers/subwoofer and have it via normal speaker connection - what setting have you got this on?

I assume all speakers and outputs worked ok on the old unit?

Bockhamptoner said:

BUT that just leaves the question of when amp is out of picture, what cables I run from the L-R outputs, down to the amp old connector and into the sub-woof in the boot

Click to expand...

If you put an amplifier in between the sub and HU outputs, then yes. But don't expect much from the HK sub, as it's probably toast by now. If it is fubar, then a suitable replacement driver is available.

Thank you all........Steering controls working
Original HU and speakers all worked, and now still do as I've changed the HU setting to 2-way Xover.
I have decided to take the KH Amp out of equation as the new HU has a better amp with more control through 13 channels of equaliser (expect a post one day to say OMG how do I configure 13 channels LOL).

I have figured out the mapping for the HK Amp pins, I hope.
Input Output to
from HU speakers
Pin 38 > 4
Pin 9 > 23
Pin 37 > 31
Pin 8 > 13
Pin 30 > 3
Pin 17 > 22
Pin 29 > 32
Pin 16 > 21

Just don't understand why this image from someone else's post has pins on one half, and mine doesn't, it's all holes.

From website Mine

And my last challenge;
HU has two phono plugs out for Sub Woofer, L - R, assuming there is a +/- in each.
The HK sub-woofer itself has four wires going in.
But on the wiring diagrams shared earlier it only shows the four wires from the amp to sub-woofer and no indication of +/- or pairs. Amp out pins 1,2,24,25. Does anyone know which are L+/L-/R+/R-?

Bockhamptoner said:

HU has two phono plugs out for Sub Woofer, L - R, assuming there is a +/- in each.

Click to expand...

Those are low level outputs, so you can't connect them straight to the sub, as you'll not hear anything.

Bockhamptoner said:

The HK sub-woofer itself has four wires going in.

Click to expand...

The wires with the black traces are the negatives.

Hmmm several posts suggest bridging hk amp but it seems that means no sub-woofer if the out from HU is not an amplified signal. So I don't understand why I would bypass amp and lose a speaker If I leave it as is ,then I assume the HK amp will filter the right sounds to the boot?

Bockhamptoner said:

Hmmm several posts suggest bridging hk amp but it seems that means no sub-woofer

Click to expand...

Not unless you add your own amplifier to power the sub

Bockhamptoner said:

If I leave it as is ,then I assume the HK amp will filter the right sounds to the boot

Click to expand...

Yes. The HK amp has got complete set of frequency control circuitry, which sends the correct sounds to the correct speakers, not just the sub.

Bockhamptoner said:

So I don't understand why I would bypass amp and lose a speaker

Click to expand...

I don't understand what you mean.

I meant why would other posts suggest I bypass the amp, emmen it works fine. So I will just leave as is. Thank you all for the advice

Bockhamptoner said:

I meant why would other posts suggest I bypass the amp, emmen it works fine

Click to expand...

Some people have strange idea's I guess. If it's working and sound comes from all the speakers, then why pull the HK amp out? I can't see any point in that at all.

Thank you, happy now, sound is brilliant steering controls brilliant, really appreciate all the input.