280i dash warning lights

[280iUSA]

Good day,
My handbrake, seatbelt, alternator (possibly others) are not working. Steve Heath wiring diagram shows power is provided from fuse 13 via a GREEN wire. However, this wire is attached to the socket of the lights, (GROUND???). What puzzles me further is the wires that connect to the base of the lamp are correct color code. The PO told me he did work on the wiring.

With respect to the alternator, does the Brown/Yellow wire provide ground to the warning light?

Would appreciate your input.

Thanks,

Millard

[Penelope Stopit]

The alternator warning light brown/yellow cable does go to negative through the alternator brushes and becomes positive once the alternator has cut-in
Green should be the fused ignition supply to any warning lights that need a positive supply such as the alternator warning light
Can you post a picture of how the other warning lights are wired?

[280iUSA]

Here's a picture.

Top left - handbrake
Top right - alternator
Middle - left seatbelt
Middle right - main beam ( this is wired seperatly)
Bottom left - brake failure RH
Bottom right - brake failure LH

Thanks for the explanation on the alternator wiring.

The green wire is daisy chained between the sockets

[Penelope Stopit]

Going by what I can see it looks like someone may have used non insulated bulb holders and then use tape or something to insulate where they fit into the apertures - anyway it doesn't really matter too much if I am not seeing things clearly regarding my mention of tape as those bulb holders are not the correct ones

Calculate how many insulated bulb holders you need - Any bulb holder that has 2 wires coming from it needs to be insulated and I think all of those have a green fused ignition wire connected to them. Any bulb holder with 1 wire going to it should earth to the dashboard metal at its aperture when pushed in, calculate how many non insulated bulb holders you need

The choice is yours - You could fit insulated bulb holders to all the apertures but the ones needing an earth to them would no longer earth when pushed into there apertures, if using insulated bulb holders that need earths you would need to loop an earth to each holder that requires one

If I was doing the job I would use insulated bulb holders and loop earths to them as this method ensures a good earth to each bulb where as relying on an earth contact at a holders push fit body is a touch hit and miss

Below are links to bulb holders, at least you can view them and understand my above explanation even if not buying from this supplier
You will need to know the size of the holes in the dashboard and possibly contact a supplier to get a match

https://www.autoelectricsupplies.co.uk/product_lis...

https://www.autoelectricsupplies.co.uk/product/458...

https://www.autoelectricsupplies.co.uk/product/457...

https://www.autoelectricsupplies.co.uk/product/699...

https://www.autoelectricsupplies.co.uk/product/719...

https://www.autoelectricsupplies.co.uk/product/855...

If I have confused anything please ask for more information

Edited by Penelope Stopit on Saturday 3rd March 09:30

[280iUSA]

Thanks for the explanation. I have attached some pics of the bulb holder for review. It appears this is an insulated holder and reversing the wires, center being Green igniton and Black/white being ground, would solve my problem.

[Penelope Stopit]

The third image looks like plastic but the lighting (excuse the pun) could be fooling me, any plastic holders are insulated and can be used for any circuit
Those other three metal holders are using the body as a connection and are non insulated
Bear in mind that if the dashboard apertures that the holders go into are plastic then none of what I have posted matters as all the holders are being Insulated from the metal dashboard by the plastic apertures, the dashboard does look metal to me - is it?

[Penelope Stopit]

Having had a closer look at the dashboard image it looks like plastic, I misunderstood it to be metal, as long as the dashboard apertures are plastic it doesnt matter what type of holders you use as they will all be insulated from one another, as long as you have holders that fit the plastic apertures you can use them

[280iUSA]

The apertures are plastic so switching the wiring should correct the problem?

Thanks

[Penelope Stopit]

280iUSA said:

The apertures are plastic so switching the wiring should correct the problem?

Thanks

No switching the wiring will make no difference, you will have to check the circuits through, you have no doubt already checked the bulbs.
It looks like the handbrake and seat belts switches will simply switch earth to the warning lights that have green ignition positives to them
Have you a diagram of the cars circuits?

[280iUSA]

I do have diagrams and they align pretty well with what I see on the car. However, the PO did a bit of rewiring which makes it challenging. I also have a lot to learn about the TVR's and truly appreciate the support and the knowledge from members of this forum.

I believe I have confused you so I drew a picture of the current handbrake wiring. In my mind wiring a bulb is straight forward, + to +, - to -. Current wiring does not match which is why I was thinking the wiring need to be reversed. What I don' t know is if there is something else going on that I am ignorant of.

Thanks

Millard

[Penelope Stopit]

I don't think you have confused me

As long as the bulb holder bodies aren't touching metal anywhere it doesn't affect the operation of any of the circuits although it is good practice to connect the green ignition supplies to the centre bulb contact rather than the body of the bulb, this is good practice as fuse 13 will not blow if a buld holder falls out of the dashboard and touches against some metal that is to earth/ground

Your warning lights have green ignition positives looped from bulb holder body to bulb holder body to......and there is no problem with this due to the bulb holders being fitted into plastic apertures

Give me a short while to post something else

[Penelope Stopit]

This is what you have


This is a better method

[Penelope Stopit]

The below is how you should achieve the above, don't loop at the holders, loop away from the holders or forget all about looping and run seperate greens to each holder

[280iUSA]

GREAT!
I appreciate you taking the time to help me solve this problem.
One step closer to getting back on the road.

Millard

[Penelope Stopit]

Glad I was able to help
It would be better to use insulated holders if you can source them