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MG Midget and Sprite Technical - No dipped beams - urgent help needed

I have to make a journey in the early hours of Friday (i.e. in the dark) and checking the car over I have no dipped beams from either headlight (so panicking). I do however have full beams (and can flash the full beams). All other lights are OK.

Any help gratefully received in diagnosing this quickly. Could this be a fuse issue or a switch issue? What's the best way to check this?

Chris (in the dark as usual!)
Chris Hasluck

Try cleaning up the earth half way down the Right Hand inner wing. I had a similar problem.

Dave
Dave Barrow

I would start by checking if there is power to the bullet connectors that split the dip power to both the headlights (dip lights powered on) - offside within engine bay at front - mine did similar due to corrosion - the new Lucar bullet connectors are rubbish chrome on steel not brass plated as originals.

richard boobier

Correction the connectors are behind the grille on the right hand side - follow the loom down the inside of the engine bay through the front panel and you should see them.

They are out in all the muck and rain so do corrode up easily.

richard boobier

You're looking for a blue wire with a red tracer.

Unlikely to be earth, as main beam is working. Also, unlikely to be fuse, as lights weren't fused as standard.

If you don't have power at the front bullet connector, you will need to check that you are getting power through the column dip switch.
Dave O'Neill 2

Bulbs? Unusual for both to go at the same time but I've had headlamp bulbs both fail within a day of each other. Must be really good manufacturing tolerances!
J Tickle

Its the dash rocker switch on mine giving aberrations at the moment. Lack of regular use. Fiddle with the connectors (push on and off a few times) or rock the switch a few times and it fixes it. More of poor connections due to corrosion methinks.
Dave Squire

Check inside the column switch cowling. The wires there do have a habit of breaking contact where they are soldered onto very flimsy brass strips. Worse if the unit is a replacement bought in the last 10 years or so. You may find that the blue/ white lined wire is flapping loose in the breeze with just a blob of solder on the end!
Guy Weller

It won't be the dash switch, as main beam is working.

Also, blue/white is main beam, not dip.
Dave O'Neill 2

Oh, the other one then blue /red is it?
Guy Weller

Checked the earth and no joy (too easy?) Now will look behind the grill (thanks Dave for the tip on wire colour).
Chris Hasluck

Checked the blue/red wire where it enters the valance and splits to the two lamps (looks like a heavy duty wire in and one heavy duty out and a smaller blue red to O/s headlight - am I checking the right thing?). Anyway, no power there so any fault must be earlier on. Does that mean it is the column switch.

I don't have the later rocker dash switch, just the old fashioned flip switch (1971 car).
Chris Hasluck

Hi Chris,

Simple to troubleshoot this with a decent 12v test lamp.



Take off the column shroud first.


One end to earth, headlamps on, check for live on the blue/red at the back of the column stalk.


If there is none, the switch is no good.


If yes, check the same wires either side of the column stalk/dash harness connector next to the steering column.


If thats good and still no power to the front loom bullet connector, the loom has damage somewhere along the inner wing, but this is very unlikely.



Good luck in findine the problem.


Regards Steve.
Steve Smith Midget 1500

Hi Steve (and others)
Thanks for the suggestions. Great minds think alike as I just did what Steve suggest and I think the column switch is faulty. I checked the blue wire entering the switch and there is power when the headlights are switched on. To the right of the blue wire is the blue/red trace wire. This has no power when the headlights are on dipped. As this is the supply to the lights this must indicate the switch is faulty. B****r - it will be difficult to obtain a new switch and fit it by end of tomorrow. Ah well, that's (midget) life I suppose!!
Chris Hasluck

Take the cowling off and check that the blue/red wire hasn't just broken off where it is soldered onto the brass strip terminal. Its easy enough to resolder it.
Guy Weller

Hi Chris,


Glad you,ve found the problem.



Might be a good idea to think about relaying the headlamp circuits to take the heavy load out of the column stalks.


The replacement switches aren't as good quality as the Lucas originals and need help to last.



Regards Steve.
Steve Smith Midget 1500

If you are not happy about doing your own relay circuit, several suppliers provide a kit with fitting instructions!
Graeme Williams

Hi Graeme
Which suppliers are you referring to. Thanks.
Chris Hasluck

Something else to consider...this is 1971 lighting and wiring vs todays run of the mill modern cars lighting

if you run what you got i doulbt anyone will notice most on comming drivers will think your normal or running halogen lights

i run my car on high britghts most of the time to watch for deer...no one even notices parking lots or on comming

my truck on the other hand gets my flashes and even a honk now and then if i dont dim

prop
Prop and the Blackhole Midget

As a temporary measure, you could swap over the blue/red and blue/white feeds behind the grill, so you have dip beam with the dip switch in the main beam position and no main beam.

Just a thought.
Dave O'Neill 2

Another temporary alternative is common the blue and blue/red in the column switch loom.



This will give you dip beam as soon as the lighting switch is in the h/l popsition and the stalk then simply turns the main beam no and off.






Theree is a more complex involving using a 5 pib relay and switching that via the column stalk but it's probaly more complex than you wiish to get involved with for one journey!



Regards Steve.
Steve Smith Midget 1500

The other common fault with aftermarket lighting stalk flashers that I suggested earlier is the little button contacts themselves getting bent. The originals seemed to be much more immune to this problem and lasted much longer.

The high and low beam circuits open and closed through tiny button contacts attached to thin springy brass strips. In time and with overheating these springy brass strips loose their springiness or get bent so that the gap increases between the contact buttons and then eventually one or other fails to connect. Or only connects intermittently which causes even more excess heat.

Its this heating of the brass contact strips that causes the flasher stalk type switches to fail and its why adding relays can prolong their life. But for a quick repair, the contacts can be bent back into position screwdriver to give them a new lease of life, at least for a few month's use.

Remove the cowl (4 screws), remove the flasher (2 machine screws) Unplug from the main loom (1 multiplug and sometimes another wire on a single bullet connector), Its then much easier with the thing in good light on the living room coffee table, to bend the contacts with a small screwdriver and check that they are all working properly than trying to do it with your head bent up behind the steering wheel in the gloom!
Guy Weller

I had the same problem not long after I put my car back on the road after a lengthy restoration. Eventually tracked to a burnt out contact in the column mounted flasher switch. As has been mentioned on here several times, reproduction parts are crap but it could also have been because I changed to halogen bulbs.
I had to buy a replacement switch but I also bought the MGOC's pre-wired Relay kit which was very easy to fit. Not had a similar issue in the subsequent 3 years.
graeme jackson

Graeme,

Halogen bulbs shouldn't be an issue if the wattage is the same, assuming you aren't using illegal bulbs of a higher wattage then the higher current might trouble the contacts over time.

Halogen bulbs are more efficient than standard incandescent bulbs and produce more light for the same wattage.
David Billington

Chris: s mentioned by the other Graeme, MGOC do one.
Graeme Williams

Thanks Graeme
I found the MGOC relay offering and a MOSS one too. MGOC is cheaper (not sure if there is any difference to explain the price difference. I think I will invest in a relay
Chris Hasluck

Chris, there are only so many manufacturers of parts for our cars. Most parts places buy from the same source. Some will charge more than another for the exact same part just because they are bigger, therefore they think they only game in town. Sometimes it pays to look around and check prices.

Cheers,
Clare
C Ravenwood

Hi Chris,


Here's a pic of my relay system attached to the LH inner wing.


I took battery power from the rear of the alternator to keep new wiring lengths to a minimum.


The 3rd one is for the cooling fan btw.


Regards Steve


Steve Smith Midget 1500

Following suggestions here I have obtained a relay kit for the headlights. The instructions are not very helpful and state "locate H/L wiring harness at end of main loom (identified by 4 way bullet connectors)". Would I be correct in thinking that this is the mass of wiring that lies on the right-hand side behind the front grill? There is no earlier point to intercept the H/L wiring?
Chris Hasluck

correct; that's why usually the r/h inner wing area is chosen to site the relays etc.
David Smith

Thanks David
Chris Hasluck

You could intercept the wiring at the connector next to the steering column which would enable you to mount the relays inside the car in the dry!
Chris at Octarine Services

I fitted the relay kit from MGOC, and ended up having an argument with them. The kit includes one in line fuse, for both the main and dipped relays, this means that one fuse blowing is going to leave you in total darkness, not a very nice thought.
I duplicated the power line from the starter solenoid, and fitted a fuse in each line, this way if one fuse blows, in say the dipped line, you would still have the option of using main beam to get to a place of safety to sort out the problem. I realize that driving on main beam would be a problem, but better that than total sudden darkness.
They stated that this was illegal.

Dave
Dave Barrow

The Moss kit also only has the one fused supply - I keep meaning to fit a second supply to allow the separate main/dip feeds/fuses as you note.

50/50 chance it could be the mains that fuse !
richard boobier

I wired mine with separate outputs from the relays, 2 main beam and 2 dipped beam, and each has a fuse. I think I am unlikely to be left with no lights - unless of course the smoke gets out of the main power feed cable to the relays, but that is fairly short and shouldn't - short, that is.
Guy Weller

Lol - my car has survived 43 years with no fuses or relays on the original loom.

You can get hold of relays with their own fuse attached - shame the kits don't use those.

Or you could get a 4 way fuse box and have each bulb filament with its own fuse.

In my experience the main issue with the headlight circuits is not the power side but the earths - these are far more likely to develop faults leading to poor light output, connectors overheating, etc.
Chris at Octarine Services

I only added relays to reduce the current through the contacts in the column stalk switch. The original was fine for 32 years. But the replacements just couldn't take the heat through the contacts, even with standard headlights. So when it came to fitting the 3rd column stalk switch in 2 years I added a set of relays. They were free from a scrapyard anyway
Guy Weller

Is there an alternative solution using LED replacement bulbs providing better light with lower current therefore avoiding the need for relays?
David Smith

LEDs seem to be quite expensive and there is some debate over their legality.
Dave O'Neill 2

Interesting - I'm aware of the costs (the light bar we borrowed for night racing costs £400-odd) but they are getting cheaper with volume production and more retail competition. Clearly legal for rear lights as they've appeared on brand new cars for several years now, I haven't heard about issues around their use as headlights?
David Smith

A pair of H4 bulbs from these guys are £100

http://www.dynamoregulatorconversions.com/led-headlamp-bulbs-shop.php

From the dynamoregulatorconversions website...


"Strictly speaking, led bulbs aren't road legal but this is really because the technology has moved quicker than the law.

We have to advise customers that all our bulbs have to be sold for off road use only."
Dave O'Neill 2

Hi agai,


As Chris says none of the headlamp circuits were fused by the factory and in all my time as an auto electrician doing classic british Mg's, Triumphs etc I've never seen a fire in the h/lamp citcuitry.


My car has relays, purely to save the switch gear from high current flows and give better voltage at the lamps.


As to the legality, its a grey area in respect of xenons and Led's. I've fitted lots of Xenons to ferraris of the 90's, 456 and 550's mostly and the MOT tester lets them go.


Strickly speaking any car with xenons should have self levelling headlamps and headlamp washers. On cars with factory xenons, if the h/lamp wash or self levelling doesn't work they come back with an MOT failure.



Steve Smith Midget 1500

Have a laugh at this
LED bar lights are legal here as long as there is an odd number of leds
13 leds legal
14 leds - no good
Now the silly bit, if the bar has a double row of leds each row has to have an odd number
6 pairs - no
7 pairs - ok

But I hear you say, that's 14 leds that you can't have in a single row
Good fun explaining that to an angry truckie when you have to knock his rego. back

willy

William Revit

This thread was discussed between 16/11/2016 and 26/11/2016

MG Midget and Sprite Technical index

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