Full Beam Failure

[Boatbuoy]

My side lights and main beam working fine. When operating the full beam button on the steering wheel the relays in the dim/dip control box can be heard to be clicking, the dashboard blue light illuminates as expected. When the headlights are on and the button is operated the main beam dips to sidelights but with no full beam. All fuses on the fuel panel are intact.

All I can think off is that BOTH bulbs have blown (?) or, more likely a loose connection.

Suggestions please....

Regards,
Olly

[sonnylad]

Have you checked both light control units above petrol tank, there is a main lighting unit and a dim dip one. very common for them to burn out on the plug in connectors.

[Boatbuoy]

Hi Russ,

Yes I'm well aware of the burn out issue, my dim/dip box has already done that. But the second box is a good shout, I've not checked that one!

Cheers,
Olly

[Warwick67]

Night time..... they'll work fine during the day

[Boatbuoy]

Russ, you were indeed correct. Another burnt out connector, this time on the Light Switching module.

Re-wired using bullet connectors and working again. Job done.

Cheers!
Olly

[sonnylad]

Glad to be of help

[Rochester TVR]

Noticed my full beam has also given up. I have exactly the same symptoms as above.

I'm going to Maplins at lunchtime so get some bullet connectors. Can anyone tell me what size I need?

Thanks

[Boatbuoy]

I ended up cutting away what remained of the plastic element of my burnt out connector leaving the bare multiple metal tangs. I then soldered some tails (short lengths of cable to the tangs) with male bullets crimped to the other ends.

I then carefully documented the colours and positions of wires into the connector on the end of the loom before snipping the wires as close to the connector as possible and fitting the females. I made labels to go on the tails and the loom wires with corresponding numbers.

The photo shows the dim/dip box, but i used the same method on both boxes and they are both still going strong!

Regards,
Olly

Edited by Boatbuoy on Wednesday 11th December 11:56

[Rochester TVR]

Ok thanks, Ill get myself a full bullet connectors kit and borrow a soldering iron.

Is it easy to see which connections are not working just by looking or do I need to get a tester on them?

(Electrical gubbins is not my area, and I need this fixed before Sunday at Goodwood).

Thanks

[Boatbuoy]

The issue is caused by poor connection between the contacts in the plastic plug. Some of the wires carry a current which is probably too high for the plug to handle. That, coupled with the poor contact and then add vibration from driving means that the contacts 'arc' or spark over and over.
Initially this will blacken the contact, but eventually it'll burn/melt the plastic (which makes a distinctive and very acrid smell).

Pull the plugs apart and look at the spade contacts in the connector on the box, if one is black you can clean it by gently scraping it with a small flat bladed screwdriver until shinny again. This in my opinion is only a temporary fix and ultimately you need to get it replaced or modified as we've already discussed, but is certainly the easiest way to see you through Sunday.

If the plastic has melted or blackened then you need to get serious with it. It's not difficult to do but is a bit fiddly and takes some confidece with a dremel to cur away the plastic. If in doubt get someone more experienced to do it!

Initial failure (dirty black contact):


Full failure (burnt/melted connector):

Edited by Boatbuoy on Wednesday 11th December 12:21

[Rochester TVR]

Thanks Olly, that is such a big help!

Im going to have a go at it when I get home tonight, fingers crossed I only have the black connections to clean up.

Cheers
Lee

[Boatbuoy]

No worries, post on here if you need any further help - but it is our works Xmas party this evening so I can't vouch for the quality of any responses after about 8pm!!!!!!!!!!!

[ukkid35]

Just taken delivery of a pair of Osram Night Breakers for £15, hope they help.

[Rochester TVR]

Last night I checked both light switching units on top on the fuel tank. To my surprise all the connections look almost brand new (previous owner partially rebuilt her).

So now I'm stumped.

My symptoms are that the button on the steering wheel does nothing. No clicking from the switching units, no full beam light on the dash...

A bit of history, my full beam has never worked but I think the light on the dash used to come on when the button was pressed. Also if it is related the washer jet button also does nothing. Steering wheel ribbon cable problems maybe?

My list things to check to tonight are.

Fuse
Bulbs
Ribbon cable (is this easy to check?)

Is there anything else it could be?

Thanks

[Boatbuoy]

If I were you I'd check the fuses, then bulbs before you investigate the ribbon cable.

The fact that you're getting no relay clicks or dash light would point to the ribbon IMO as it's a known failure point, however once you've got it all apart to check you might as well change it anyway. It's a fiddly job!

[Rochester TVR]

I've found out why my main beam doesn't work... I don't have a 'dim / dip switching unit' as pictured above.

All I have is a lonely unconnected plug. So now I need to find a new one.
I'll try the eBay and the usual tvr parts sites.

Guess this is a bespoke tvr part and my wallet is about to be fleeced!

[sonnylad]

I would have a good look behind the fuel tank just incase it has fallen behind, i had that happen to one of mine. Lucky for me as it stayed connected to the wiring loom so was easy retrievel.

[Boatbuoy]

Rochester TVR said:

I've found out why my main beam doesn't work... I don't have a 'dim / dip switching unit' as pictured above.

All I have is a lonely unconnected plug. So now I need to find a new one.
I'll try the eBay and the usual tvr parts sites.

Guess this is a bespoke tvr part and my wallet is about to be fleeced!

Currently 2 on ebay (both from the same vendor) for a buy it now price of £50:

http://www.ebay.co.uk/itm/TVR-ME0161-DIM-DIP-SWITC...

http://www.ebay.co.uk/itm/TVR-ME0161-DIM-DIP-SWITC...

[Rochester TVR]

Boatbuoy said:

Currently 2 on ebay (both from the same vendor) for a buy it now price of £50:

http://www.ebay.co.uk/itm/TVR-ME0161-DIM-DIP-SWITC...

http://www.ebay.co.uk/itm/TVR-ME0161-DIM-DIP-SWITC...

Well spotted thanks! I had seen one for 3 times that price at a well known TVR garage!