Electrical issues - Land Rover 110 2.5 n/a upgrade to 300Tdi

[Paul butfustet]

Back story

I took on an old '85 110 H/T 2.5 n/a with a broken chassis and replaced the chassis (family thought I was mad). Then decided to go for a 300tdi/R380 upgrade plus secondhand looms (engine, bulkhead and chassis). Now 3 years later (and plenty of cider) I've layed in the looms and started testing what works and doesn't before fitting the dashboard and body panels like wings and seatbox/floor panels etc. Tub on chassis.

Good points

She starts on a flick of the key, runs and sounds lovely, so very happy. I have oil pressure, ignition and glow warning on at position III of key.

Not so good points

No indicators (Hazzards work). Power on the purple, not on the green with ignition on position III. In the socket.

No head lights at all. Power comimg in to the light switch, then power to the other 2 switch contacts for the side and head lights.

No blue tell tale either (for hi beam) so swapped the bulb (which is working). No difference

No horn.

Rear Fog light works only if holding down the spring loaded rocker switch (headlight switch must be on and tell tale is illuminated). 

Haven't fitted the wiper switch or gauges/instrument light loom yet because I bought 300Tdi ones, with plastic multi connectors, but the loom must be an early version because I need the ones that fit a 200Tdi (the black rubber blocks). I should have checked, but assumed a 300 loom would be a 300. That's how much I know.  Still need to get hold of them.

I used second hand looms so don't know what worked or not. I also don't know what should be there or not as far as components. Not easy to find the correct wiring diagram.

Please, I need help. If anybody can give me a step by step guide so I can navigate my way through checking the current flow and components (header joints/switches/relays) etc., that would be great. I have a multi meter, hammer and 5 gallons of cider. Just in case I need to pull the bulkhead loom off.

Seriously, if anybody can help, I will be extremely grateful.

Cheers, Paul

 

[pete3000]

Was it originally ex military? the loom may have some extra features which need to be linked out or adapted. e.g 6 way light switch and convoy lights.

I did mine over 10 years ago and changed the fuse box to blades at the same time, 2.5 nad had glass fuses which are blow current rather than holding.

 

Pete

Edited February 19, 2022 by pete3000

[pete3000]

Most of the faults you list above though are the indicator horn and high beam, all of which are on the indicator stalk. Lights should appear on the dash switch which is fed with Brown, then switched red for side and blue for dipped/main. Depending on the stalk position. Head lights should have fuses for each side and for dipped and main beam.

https://rimmerbros.com/Item--i-AMR6104P--SelectedCurrency-1?gclid=EAIaIQobChMIqo6mwsKL9gIV0uvtCh0HmQlsEAQYAiABEgL7o_D_BwE

[Paul butfustet]

2 hours ago, pete3000 said:

Was it originally ex military? the loom may have some extra features which need to be linked out or adapted. e.g 6 way light switch and convoy lights.

I did mine over 10 years ago and changed the fuse box to blades at the same time, 2.5 nad had glass fuses which are blow current rather than holding.

 

Pete

Hi Pete, no standard 12v with glass fuses. I've removed all electricals and replaced all looms with second hand 300Tdi

[Paul butfustet]

Update on hazzard/indicators this morning

I wanted to check the ignition current on the green - still no current.

I jumped from purple to the supply to flasher light green and the stalk blow the indicator fuse when I moved it down for left turn. Replaced the fuse and checked the hazzard fuse and now no hazzards (which worked before this test).

The fuse has the thick brown and thick white. There must be a short somewhere??? 

[western]

As the looms are used, that may of been the reason they were removed from the original vehicle. 

[Paul butfustet]

2 hours ago, western said:

As the looms are used, that may of been the reason they were removed from the original vehicle. 

Yes always a risk I know. I couldn't see any obvious damage it looked ok. I'll pull the loom off and trace the wiring and look for any damage. If none I'll try to test the flow of current through the hazzards/indicators and headlight circuits. There is already a short somewhere and no current on the ignition green.

 

[western]

A continuity test would find broken wires. 

[pete3000]

pull the rear half of the loom with the connector loom which runs through the chassis to the rear, at least you'll know if the front half has the short.

[Eightpot]

You may have a connector in the loom behind the dash binnacle for the dim/dip relay, which either needs a dim/dip relay installing or bridge the terminals with a short loop of wire.  Do a search on this forum for dim/dip relay. If you don't have this relay or bridging wires, you'll have no lights.  

Hazard switches can be fickle things  - before you go to great lengths try another good switch first, indicator circuits run through this switch and nine times out of ten its the culprit, followed by flasher relay on fuse panel.

The horn has a purple 12v+ to one terminal, black wire on other terminal runs back to the horn stalk. Inside the horn stalk is another wire attached to earth - pressing the button pushes a copper contact across the two wires, making the circuit.  Quite easy to fault find on that circuit.

No  blue tell tale for high beam may be a bad printed circuit on the back of the instrument warning cluster that the bulb holder sits in,  if high beam is actually working - easy to check with a multimeter if voltage is present at the connector block and making its way across to the bulb.  If high beam not working, its usually the switch.

Rear fog lamp problem sounds like a faulty switch

 

Edited February 20, 2022 by Eightpot

[Paul butfustet]

Manythanks for the replies. To answer some of the suggestions, when I first discovered the problems this was the situation:

 

Lights:

side lights - No Ign on - front/rear LH/RH all working and relay behind gauges click

Headlights - None - just a click of the relay

Hazzard - with Ign off and switch on - all indicator lights flash

Hazzard - switch in off position and Ign ON - nothing

I jumped the purple to the socket terninals G/R G/W LH RH indicators and got the front and rear pairs continuously 

I tested the Green terminal in the socket with Ign On for current and nothing there.

Yesterday I wanted to test the indicator stalk so I jumped from purlpe to the supply to flasher socket terminal and it blow the indicator 15A fuse when I did down for left turn. I put another fuse in to test Up for right turn -No fuse blown but no indicators.

I tested the left again and it blow the fuse again.

After this I have no sidelights or hazzards or this (the purple to the socket terninals G/R G/W LH RH indicators and got the front and rear pairs continuously)

 

[western]

300Tdi wiring diagrams.  these should help. 

there is NO relay for side/tail lights.

remove the Pink cased [dim dip] relay & join with a jumper wire the 2 blue/red trace wires in the relay socket. that should get your dip beam headlights operating.

LR actually sell a dummy relay which does this job, its also pink cased but just joins the 2 wires mentioned together.

https://parts.jaguarlandroverclassic.com/ywz10003l-control-unit-dim-dip.html

https://rimmerbros.com/Item--i-YWZ10003L

if that doesn't work then I would replace the main lighting switch as well.

[Paul butfustet]

On 2/20/2022 at 7:42 PM, western said:

300Tdi wiring diagrams.  these should help. 

there is NO relay for side/tail lights.

remove the Pink cased [dim dip] relay & join with a jumper wire the 2 blue/red trace wires in the relay socket. that should get your dip beam headlights operating.

LR actually sell a dummy relay which does this job, its also pink cased but just joins the 2 wires mentioned together.

https://parts.jaguarlandroverclassic.com/ywz10003l-control-unit-dim-dip.html

https://rimmerbros.com/Item--i-YWZ10003L

if that doesn't work then I would replace the main lighting switch as well.

I'v been trying to find an early Defender 300TDI wiring diagram 95-96

I've looked at another loom (a later model, has lots more connectrs for things, alarm, AC,etc) I saw a rear fog lamp ecu on it that goes behind the gauges. A white transparent square 4 pin connector. I don't see this on my loom, except a similar connector but a bit smaller. I see that there's a headlight feed that goes into it.

Does anybody have or know if the first of the Defender 300Tdi's had this one touch pulse ecu for the rear fog lamp? Did LR move the fog lamp switch from the column to the 3 gang located on the dash end lower corner?

Today I checked things again.

No headlights (but all side lights) 

I jumped pins 2 and 8 - nothing

Hazzards on, Ign off - all 4 ind flashing

Indicators - hazzards off, Ign on - column stalk switch Up      - nothing

                                                      - column stalk switch Down - blows ind fuse (big short)

I checked the Hazz socket - purple 12v,   Ign On green 12v,  jumped from both of these to the GR and GW left right indicators working in pairs front and back, no flash obviously.

I checked continuity from the fuse (green) to the green in the multi connector for the column stalk switch, that was fine.

Does this mean that the stalk is wired wrong (I bought this new) I can't see how the green/brown can be at fault because it's getting power as the out from the flasher relay for the hazzards.

Just had a thought, can I jump the wires in the column stalk socket, if I can identify the wires (left and right hand indicators) that run to the flasher this should cause the short and blow the fuse or if it doesn't it mean the new column stalk is faulty. Am I thinking straight on this?

Grateful for ant help. Cheers, Paul

Edited February 22, 2022 by Paul butfustet

[Peaklander]

Here's an older diagram

Defender 300TDi Wiring Diagram.pdf

 

[Paul butfustet]

Ok cheers, this looks interesting. Many thanks. I see that there is a rear fog light inhibit relay and a rear light relay. There certainlt aren't many relays on my looms. There definately isn't a rear fog light inhibit relay. Is the this rear light relay the yellow one next to the starter relay on the fuse box? Cheers, Paul

[Peaklander]

Mine is a '96 and I always refer to the later diagram rather than the one I provided. The fogs need to be interlocked with the headlamps and on the later circuit you are correct that it shows this as an 'ECU' at connection C543. This is apparently behind the facia - so near the instruments. I can't say that I have seen this but neither have I seen a standalone relay for the fog 'enable' as shown in that earlier diagram. The yellow ones are heated rear window, headlamps and the starter relay.

Not much help I know.

Here is another file showing the locations of the connectors. First pick one on the later circuit diagrams, eg C543 and cross-reference it in this 'library'  to find where they are located on the vehicle. Use the search in the pdf. That helps find them in the loom.

Defender_Electrical_Library.pdf

[Paul butfustet]

Many thanks for this. Great detail on exactly where the wires run and what components are on the harness. This is exactly th ediagram for this other loom i saw a few days ago. Is there a document for an earlier def 300 loom?

Mine definately doesn't have the rear fog light ECO multi connector. No door switches for interior light. No headlamp voltage regulator and the fuse box onlty has the 2 yellow relays. No wiring for alarm or A/C or rear wash/wipe or neated rear screen etc. The fuses are layed out differently than this one. My Headlight/sidelight fuses are on the lower row running left to right 4 x 7.5amps 2 x 5amps....... The instrument/gauges still use the early rubber block connects and same for the wipers.

I will buy a new pink headlight dip relay, behind the gauges. But still need to solve why the left indicator blows the indicator fuse and also why not the right. What's strange is the wires to the connector for the indicator stalk don't have the green/red or the green/white for the indicators where the newer version of the loom does. 

Cheers, Paul

[Paul butfustet]

Update

I managed to swap out the bulkhead loom for a later model version from a friend (has the little blackbox rear fog light ecu, separate left right indicator warning lights and different fuse layout). Everything works except the instrument lights and RH side/tail lights. Fuse is ok, I did a continuity test on it. I have no current feed into the fusebox so I will trace the wiring. Must be a break somewhere. Even shows just under a quarter of diesel in the tank (which is about right. I fitted a new tank and put 20 litres in it. I'll solve this light problem and let you know know. I can then fit the dash etc. Seatbox, seats, handbrake, floor panels and then the front wings, slam panel and rad surround and the bonnet. I'll take a look at the other bulkhead loom, should be easier to test now it's out. I'll wait til it's a bit warmer and sit in the garden with a gallon of cider.

[Peaklander]

Presume it’s a TD5 if there are two circuits for the indicator warning.

Please post a pic of that fog black box. I’m still wondering just how mine is wired-up. 

[western]

Late 300tdi had seperate indicator warning lights with bulbs, Td5 & ROW 300Tdi had warning light panel that is all led lit. 

[Peaklander]

Thanks @western, I didn't know that. Is it a double bulb holder that fits in the same space as the single one? @Paul butfustet, that looks like a thatched roof. What a nice space!

[Giles]

26 minutes ago, Peaklander said:

that looks like a thatched roof. What a nice space!

I was thinking exactly that too !

[western]

10 hours ago, western said:

Late 300tdi had seperate indicator warning lights with bulbs, Td5 & ROW 300Tdi had warning light panel that is all led lit. 

No the are 2 seperate warning lights that flash green with a left or right white arrow. 

 

 

[Paul butfustet]

14 hours ago, Peaklander said:

Presume it’s a TD5 if there are two circuits for the indicator warning.

Please post a pic of that fog black box. I’m still wondering just how mine is wired-up. 

I put a 300Tdi in with an R380. It was a 2.5 n/a.

Plenty on ebay part no. YWC104430

[Peaklander]

OK, thanks. I am sure I don't have that, at least not up at the instruments. I'll look at the back of my switch, there must be something on it and it's good to know how things are configured.