Yaaaaayyyyy..... Ah Wait! Aww Feck!!! HEVAC.

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Doo

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So I got the new (not new) interior, heated electric seats with all the wiring to the BECM....except I didn't!

:(

Had the lad with me and of course removing stuff (well, not me, but I had to know what went where and how, so the chap generously waited so he could show me and keep me right as to how it went back together) takes a while. But the previous owner had installed a PS2 with all the associated wiring and some of it was put through the carpet with holes drilled where they had put a wire through then soldered wires and taped them up. Chasing that was a mare! It got to the point where I said just cut them. I know enough about AV to know what to do when it comes to fitting it all in George.

Anyway, what I'm trying to say is, my lad nipped and nipped and nipped our heads to the point where I called it a day and while the chap packed the carpets in my car I thought I had everything...

As it turns out I forgot the wiring from the HEVAC to the BECM (along with the heated windscreen) so I have appealed to the chap (and I'm pretty certain he will come through). to undo it and send it.

I did get the appropriate HEVAC with all the extra buttons, bells and whistles.

My question is, is that part easy enough to separate from the rest?

I have the part of the loom that powers the seat motors from the BECM, but obviously I need the part that operates the heating elements.

My other question is, the heated screen. Where does the wiring from the screen go before it connects to the HEVAC?

And any other relevant questions I have forgot to ask may be added by those wot knowz :D

Fank ooo :)
 
And might I add, 320 miles round trip on LPG without missing a beat :)

I had to do the odd full on overtake of wagons an wonders (as in "it's a wonder they have a licence) because the A9 is riddled with ASC's so 53mph is the new 60mph. I set my cruise at 60mph and would happen up behind one of the brake check brigade, so it would be a case of foot down and out...

Anyhoo, all the way home I sat at 62mph, The whole 159 miles o_O But the report is she was faultless. Absolutely faultless. No hint of any issues and the feeling of power, torque and reliability the whole journey was....frightning :eek::p

I mean, who ever heard of a reliable P38 :D
 
RAVE is your friend. If you did not have electrically adjustable heated seats, Sunroof Etc fitted as standard, you may have a low line BECM others may know but it may not service heated seats. I am not sure.
 
Heated windscreen goes via the engine compartment fuse box and relays. You may find the wiring from the screen to the fuse box is already there.
I'm pretty sure that the Lo Line BECM does not support electric seats but it's not difficult to rig them up as stand alone.
 
Datatek said:
Heated windscreen goes via the engine compartment fuse box and relays. You may find the wiring from the screen to the fuse box is already there.
I'm pretty sure that the Lo Line BECM does not support electric seats but it's not difficult to rig them up as stand alone.
Click to expand...

The switches for heated seats on the HEVAC are momentary, power to heaters comes from BECM. As said i don't think lo line BECM will do that.
 
My BECM is a haitch...and an big "H: on the sticker.

My car also has electric height adjustment. The back & forth and tilt are manual.

I also have front fog lamps, so again, attributed to the Hi Line BECM, no??

I found wiring under each side of my windscreen, so assumed all was in place apart from the HEVAC.

So, if the wiring is there and there's nothing missing in the fuse box (as in all relays present) does that mean I only have to "tell" the BECM to get with the programme and accept it has a job to do??

And yes I know the electronics in the BECM operate built in relays on the circuit board. Good idea, pity it's very old technology. But, easy enough to fix if one can find the components. I'm handy with a soldering iron.
 
Doo said:
My BECM is a haitch...and an big "H: on the sticker.

My car also has electric height adjustment. The back & forth and tilt are manual.

I also have front fog lamps, so again, attributed to the Hi Line BECM, no??

I found wiring under each side of my windscreen, so assumed all was in place apart from the HEVAC.

So, if the wiring is there and there's nothing missing in the fuse box (as in all relays present) does that mean I only have to "tell" the BECM to get with the programme and accept it has a job to do??

And yes I know the electronics in the BECM operate built in relays on the circuit board. Good idea, pity it's very old technology. But, easy enough to fix if one can find the components. I'm handy with a soldering iron.
Click to expand...

Look at RAVE for wiring details.
 
wammers said:
Look at RAVE for wiring details.
Click to expand...

I tried, it doesn't appear to "like" my laptop!

But the wiring up isn't the issue, I am simply asking if the HEVAC wiring on the donor car goes straight to the BECM or will there be other wires spliced in with it?

The seat motor loom came out beautifully so that's what I'm hoping for with the HEVAC loom...
 
Datatek said:
Have you pulled your current HEVAC out? You may find that all the wiring is there, unless it is a non aircon one.
Click to expand...

I have A/C and the current seats do not have heating, which is why I went to get the whole interior with bells & whistles and insisted on the HEVAC with the extra buttons.

I'll have a look see behind my current HEVAC because there are a couple of bulbs gone anyway.

Thanks :)
 
Doo said:
I have A/C and the current seats do not have heating, which is why I went to get the whole interior with bells & whistles and insisted on the HEVAC with the extra buttons.

I'll have a look see behind my current HEVAC because there are a couple of bulbs gone anyway.

Thanks :)
Click to expand...

If you have not got RAVE you are going to struggle. Heated seat request momentary switches, outputs come from pins 11 and 12 on socket C246A (pre 1999) C1576 (1999 on). If you look down on HEVAC at sockets on back with screen pointing away from you. That is the small socket at the left hand side. Pin 12 is at the top right corner pin 11 one in from it. Pin 11 should be Black/purple wire, pin 12 should be Black/red wire on plug. If you have those on the plug that goes into the socket you have half a chance.
 
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wammers said:
This is from Nanocom site will give you an idea of where various wires and plugs go. https://www.nanocom-diagnostics.com/downloads/preview/p38-becm
Click to expand...

Trying to scan through it just now (but my eye pain flared up again, it's like 20 eye lashes made of wire stuck in there and blinking is agony, looking around is agony, bright light such as TV. laptop, phone, wife's smile, all agony) Seems to be a very well written article from what I gather so far.

Thank you Wammers, very helpful.

Crimbo salutations...:)
 
Well now, here's a thing... I decided to chase the seat wires in my car and noticed in my seat loom, I have a green plug in the tunnel side of the BECM for my up/down motor in my grey seat. There is also part of the loom goes to the passenger seat, but it isn't electrically adjustable so why the wires?? o_O

Anyway, on the other seats, the loom has one extra plug and I had the socket on my BECM. So I unplugged my loom, plugged in the other loom and everything fitted just fine.

I had a feeling that if I removed my seat and put the all electric seat in, it should work.

So I did...and it did :cool:

I set the positions and set the memory. All good. However, the damn mirrors dipped and wouldn't come up without help, so I disabled that function (I hate dipping mirrors anyway because I can actually drive and don't need them :rolleyes:).

So tomorrow when my buddy comes over he'll be helping with the passenger seat too :D

I'll be installing the HEVAC too as mine needs a little clean & some bulbs so it'll be a good excuse to see if there's anything missing. I know there are wires in place for the heated screen so that's half the battle.

It's all good :)

Shite picture, battery was dying and it wouldn't let me use the flash :rolleyes:

xIQXu3e.jpg


Need something to clean the mankyness off the leather, any recommendations??

My pal is going to deal with the carpets. :)
 
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Well now, here's a thing... I decided to chase the seat wires in my car and noticed in my seat loom, I have a green plug in the tunnel side of the BECM for my up/down motor in my grey seat. There is also part of the loom goes to the passenger seat, but it isn't electrically adjustable so why the wires??
Not heard of Left hand Drive?
Lots of good leather cleaners, Google is your friend.
 
Datatek said:
Well now, here's a thing... I decided to chase the seat wires in my car and noticed in my seat loom, I have a green plug in the tunnel side of the BECM for my up/down motor in my grey seat. There is also part of the loom goes to the passenger seat, but it isn't electrically adjustable so why the wires??
Not heard of Left hand Drive?
Lots of good leather cleaners, Google is your friend.
Click to expand...

Left hand drive!! What witchcraft is this ?
Upon further searching, it would appear my old seats have heating elements (which explains the extra wires) but clearly the HEVAC has been replaced with a non heated seats version!!! o_O

It may go some way to explaining the seats working without needing programming (the up /down switch is partial electric I suppose).

Anyway, the reason I asked about leather cleaner is to get members opinion on what they used and perhaps what to avoid... Google can't always tell me what Big Davey tried or our own Lord Hippo ;)

Anyway, thought I'd share my experience in case someone else has strange goings on with their 38's :p
 
Doo said:
Left hand drive!! What witchcraft is this ?
Upon further searching, it would appear my old seats have heating elements (which explains the extra wires) but clearly the HEVAC has been replaced with a non heated seats version!!! o_O

It may go some way to explaining the seats working without needing programming (the up /down switch is partial electric I suppose).

Anyway, the reason I asked about leather cleaner is to get members opinion on what they used and perhaps what to avoid... Google can't always tell me what Big Davey tried or our own Lord Hippo ;)

Anyway, thought I'd share my experience in case someone else has strange goings on with their 38's :p
Click to expand...
I use Glyptone leather products.
 
Datatek said:
I use Glyptone leather products.
Click to expand...

Ahh, ok. Can't say I've heard of it up these parts. I'm fond of Autoglym, but not so fond of the price. That said, it's tar and bug remover is superb, so perhaps I should try their leather cleaner.

Anyhoo I got the passenger seat in and the HEVAC works...after a fashion Needs new bulbs for the rocker switches and the fan speed control Heated seat switches work (light up & click from the control pack inside the front door). The speed controller is superb. Smooth linear and positive action with each click showing as one notch of speed on the screen. My old one you had to spin it over and over!

So I'm just doing the light stuff now, door cards and what not. I also need to solder the airbag wires and repair the seat heater elements. The latter will have to wait till next year when one of the Facebook P38 forum members is supplying a kit Inc tools, thermostats and element repair items.

All in all enjoyable day...
 
Doo said:
Ahh, ok. Can't say I've heard of it up these parts. I'm fond of Autoglym, but not so fond of the price. That said, it's tar and bug remover is superb, so perhaps I should try their leather cleaner.

Anyhoo I got the passenger seat in and the HEVAC works...after a fashion Needs new bulbs for the rocker switches and the fan speed control Heated seat switches work (light up & click from the control pack inside the front door). The speed controller is superb. Smooth linear and positive action with each click showing as one notch of speed on the screen. My old one you had to spin it over and over!

So I'm just doing the light stuff now, door cards and what not. I also need to solder the airbag wires and repair the seat heater elements. The latter will have to wait till next year when one of the Facebook P38 forum members is supplying a kit Inc tools, thermostats and element repair items.

All in all enjoyable day...
Click to expand...

The stuff you use on your leather Gimp suit maybe ok try it on a unseen part. ;):D:D
 
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