Page 1 of 1

DHC v FHC wiring

Posted: 03 May 2014 11:56
by dursleyman
I have owned my old red 1980 TR7 DHC for about 12 years and it has always had a redundant heated rear window switch with its wiring in the dash. I didn't think much of it, just thought a previous owner had replaced the switch panel and never bothered to remove it.
On my "new" 1981 DHC I will be fitting an electric fuel pump so thought I could maybe use the heated window wiring to supply the pump, and using the switch in the dash could be a safety/anti thief measure. When I had a look today there does not appear to be any wiring for the heated window in the loom behind the switch panel.
Did Triumph actually produce two different looms for the DHC and the FHC cars? I would have thought it was cheaper to use a standard basic loom and just add the various extras as required. I now think the previous owner may have replaced the loom with a FHC one.

Russ

1980 TR7 Sprint DHC, 1981 TR7 Sprint DHC
Dursley
UK

http://tr7russ.blogspot.co.uk/

Image Image[img]http://i1040.photobucket.com/albums/b410/dursleyman/TR7%20web%20picture/IMG_0479-Optimized.jpg[img]

Posted: 03 May 2014 20:24
by nervousnewowner
my 81 dhc had wiring for a heated rear screen in the loom, so you could hook up the heated rear window off the hardtop into it, I sliced mine out when slimming the loom down at one point thinking the wiring was redundant, didn't realise the white wire to the switch sent power to the gauges too until I cut it and found nothing worked on the dash...lol

so has the sprint engine come out and the red dhc been carted off then?

project dhc sold sadly, but project fhc taking over... Dave...
Image Image
1977 TR7 FHC awaiting restoration
1998 Celica 1.8 ST back to my current car
1998 mk 2 mondeo 1.8 blew engine up..... long story...

the new project at birth, watch it evolve...I hope...

Posted: 04 May 2014 13:43
by busheytrader
Hi Russ,

UK DHC's and FHC's of the same year have the same loom. I've used the redundant heated rear window wiring on my DHC, for an accessory run off a fog light switch beside the original fog light switch.

There should be a white connector block with the HRW wiring sitting behind the blanking panel waiting for a switch to be mated to it. Mine was there fitted with the tiny bulb that illuminates when switched on.

I won't tell anyone if you want to run your fuel pump off it as a security device if you don't. [:D]

Adam

Image Image

TR7 V8 DHC Jaguar Solent Blue. 9.35cr Range Rover V8, Holley 390cfm, JWR Dual Port, 214 Cam, Lumention, Tubular Manifolds, S/S Single Pipe Exh, 3.08 Rear, 200lb Spax & PolyBushes all round, Anti- Dive, Strut-Top Roller Bearings, Capri Vented Discs & Calipers, Braided Hoses, 4 Speed Rear Cylinders, Uprated Master Cylinder & Servo, AT 14" 5 Spokes or Maestro Turbo 15" Alloys, Cruise Lights, S/S Heater Pipes, Replacement Fuel Tank. No Door Stickers. Mine since July 1986, V8 from 1991 courtesy of S&S V8 conversion and big brake kits.

Posted: 04 May 2014 21:29
by dursleyman
Thanks guys you confirmed what I expected, but I did not find that redundant plug just a taped off purple wire. Somebody has been here before me - big surprise. If I read the diagram right the purple wire should be ignition services? Have to do some tests tomorrow.
Watch this space.

Russ

1980 TR7 Sprint DHC, 1981 TR7 Sprint DHC
Dursley
UK

http://tr7russ.blogspot.co.uk/

Image Image[img]http://i1040.photobucket.com/albums/b410/dursleyman/TR7%20web%20picture/IMG_0479-Optimized.jpg[img]

Posted: 05 May 2014 05:25
by john 215
Hi,

Still common practice today, one loom across the range. They have dedicated looms for petrol or diesel but other than that the same. Fitted a complete harness to a flood damaged E64 6 series with a low spec, had loads of un-used plugs everywhere !! Not good when you have a terrible memory !!

My DHC has same spare connectors ,sub. looms would be different though like heater and A/C and engine bay etc.

Not going say what I used mine for [:p]

Cheers John

ImageImageImage Image
LIVE LIFE A QUARTER OF A MILE AT A TIME!

1976 Speke FHC Beauty Now with an overdrive conversion

1979 3.5 FHC(STATUS PENDING!!)

1982 2.0 DHC NOW A 4.6, BUILT NOT BROUGHT !!!!

Posted: 05 May 2014 15:04
by dursleyman
Looked at the wiring diagram properly and realise that purple stuff is generally permanent live but via a fuse, so not what I want. I'll need to go looking for a white ignition live feed to source from unless I can find what the PO did with the heated rear window cabling.

Russ

1980 TR7 Sprint DHC, 1981 TR7 Sprint DHC
Dursley
UK

http://tr7russ.blogspot.co.uk/

Image Image[img]http://i1040.photobucket.com/albums/b410/dursleyman/TR7%20web%20picture/IMG_0479-Optimized.jpg[img]

Posted: 05 May 2014 18:23
by john 215
Hi Russ,

Lucas have used for years a basic set of colours for different jobs on the car's that used there looms -

A rough guide on this PDF ( not always gospel but normally the case ) -

http://www.autoelectricsupplies.co.uk/c ... rder_2.pdf

When I moved from Rover to VW dealership it took me ages to rid my head of Lucas wire codes, for instance Lucas Brown is battery live, on German car's its earth, it don't get much more opposite [:0]

Cheers John


ImageImageImage Image
LIVE LIFE A QUARTER OF A MILE AT A TIME!

1976 Speke FHC Beauty Now with an overdrive conversion

1979 3.5 FHC(STATUS PENDING!!)

1982 2.0 DHC NOW A 4.6, BUILT NOT BROUGHT !!!!

Posted: 05 May 2014 23:25
by dursleyman
John that is excellent stuff, just what I needed. I know quite a lot of the usual ones like the ignition and headlamp colours after 40 odd years of tinkering with British cars but your chart is the perfect addition.

Russ

1980 TR7 Sprint DHC, 1981 TR7 Sprint DHC
Dursley
UK

http://tr7russ.blogspot.co.uk/

Image Image[img]http://i1040.photobucket.com/albums/b410/dursleyman/TR7%20web%20picture/IMG_0479-Optimized.jpg[img]

Posted: 06 May 2014 19:29
by kstrutt1
I used the hrw switch for the same purpose on mine, worked fine until the switch gave up and left me stranded by the side of the road last week!

Posted: 08 May 2014 15:16
by dursleyman
Update, I just collected some new TR7 body panels from a guy - two new front wings, two front wing repair panels and two new doors.
He also had a box of interior stuff. Amongst it is a dash loom complete with the missing HRW plug wiring, so I can just swap it for mine if I need to.

Been out and compared the new bit of loom with the one in my car so I could see where the missing bit should be and guess what - I found it - carefully hidden under some self amalgamating tape. So its game on for that fuel pump feed.

Russ

1980 TR7 Sprint DHC, 1981 TR7 Sprint DHC
Dursley
UK

http://tr7russ.blogspot.co.uk/

Image Image[img]http://i1040.photobucket.com/albums/b410/dursleyman/TR7%20web%20picture/IMG_0479-Optimized.jpg[img]

Posted: 10 May 2014 04:36
by john 215
Hi,

<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><font color="red">So its game on for that fuel pump feed.</font id="red"><hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">


Or the earth of the fuel pump relay, some have done that mentioning no names [;)]

Cheers John

ImageImageImage Image
LIVE LIFE A QUARTER OF A MILE AT A TIME!

1976 Speke FHC Beauty Now with an overdrive conversion

1979 3.5 FHC(STATUS PENDING!!)

1982 2.0 DHC NOW A 4.6, BUILT NOT BROUGHT !!!!