Talk Morgan Forums Morgan Sports Cars Morgan Aero 8, 2012< Plus 8, SuperSports, Coupe & Aeromax Another Issue with electrons...

Saturday morning we did our weekly " Morgan bulb check".
Everything at the back and sides working correctly, but at the front the O/S indicator was not working.
Quick replacement of the bulb. That didn't help, so I swapped it for the known good N/S bulb. Yup, it wasn't the bulb.
Wheel off, strip the wiring, then clean the connectors right back from the back of the lamp holder back to where the two wires come out of the main loom..... The connectors look fine, but with the indicators set to flash there is no voltage...



Does anyone know what to look for next?
Could it be a fault in the wiring blocking those beloved electrons?
I've exhausted my ability to correct the fault...a nice drive to Williams next week!

try a test lamp on the feed wires from the loom ?

If the test lamp works, it is probably a dodgy/corroded connector in the back of the bulb holder....

James

If the rear o/s is not illuminated or flashing then the front won't be Peter. You need a certain electrical load collectively achieved from front and rear for the indicators to flash correctly, so measuring with what will be a high impedance voltmeter may not show 12 volts without a bulb at the front.

Suspicious are the wire colours in your pic from main chassis loom. To conform even by MMC standards the cables to offside indicators should be green/white and black. Your pic suggests two core mains cable has been used

Only thoughts are based on what I recall as your mention of Tarka being an MMC development car. Difficult to see but have the cables been extended and poor connection taped up where it exits from loom convoluted protection?

I agree re the fault symptoms of a bulb.

On the Coupe when the front wing bulb failed the remaining pair worked but went at a higher rate I believe.

Maybe a late thought for this situation but are you certain you have not had mice in there having a random lunch around the cabling ? Any signs at all.

I have two of those electric squealing things plugged in because of concern around this. We are just up the hill from the River Test and they have been seen around various back gardens etc.

Perhaps the simplest test could be to select ohms on your meter and check that you have a resistance across the two wires going to the indicator lamp holder with the lamp in place..? If not with the meter still connected try removing and replacing the bulb and see if it the reading alters...

Another posibility is to connect a 12 volt supply across the same two wires to see if the indicator lamp lights up.. and if not, with the 12 volts still connected again try removing and replacing the lamp, if it flickers and fails to stay lit during the replacement process then you may have a corroded bulb holder connection... either live, earth, or both.

Of course the earths ever tend to be the prime suspect and a cruddy lamp cap can be cleaned up with a rub of steel wool to testore connection to the metal of the lampholder where it picks up it`s earth.

Sometimes the lead contact on the centre of the lamp cruds up, or that which it connects to in the centre of the lamp holder, where a scrape with the blade of a screwdriver can restore connectivity...

Good luck Peter, you will get there.

I thought you had CANBUS light checks on the +8?

I would have thought you'd have a lamp on the dash?

Is your indicator circuit fused? I would not expect the indicators to be fused normally as they are such short usage lamps powerwise but if they are then check the fuses.

It could be the flasher relay output at fault?

Canbus works only on the stop lights and side lights, not the indicators.
I was wondering about the flasher relay, but as 5 of the 6 indicators work as normal I thought not.
Luddite has given me a check list... which I'll let Williams deal with.

Have you investigated the blue and brown cables from loom Peter? Just to reiterate this doesn't appear to be wiring that MMC would normally have sanctioned. Very easy to just cut back what looks like insulating tape and check for any botched connection.

I've ordered a new bulb holder part from Librands...then will asl Williams to install it.

Happy to drive it otherwise.... the wing repeater works, as does the rear, so according to the specialists it is most probably corrosion deep in the bulb holder.

I may take the car out, tomorrow.

When the new holder and bulb arrives I suspect I would attach it to the wires and hopefully see it flash as it should if that is the cause of the issue..?