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-   -   Light gremlin? (https://www.the75andztclub.co.uk/forum/showthread.php?t=295883)

Dorchester2 19th May 2019 19:07

Light gremlin?
 
Back from Brittany.
Lovely week with 4 days in a row with a brilliant sunshine, cool in the early morning but rather warm enough along the day.
Lots of castles & gardens visited.

My pride & joy was a very bliss during those 2k km (1.3k mls) but...
a gremlin on sentry duty...

That time he was nested in the light electrical system but... everything was fine, all the lights perfectly working but that stubborn message on the computer screen telling me sometime a front bulb was failing, sometime a rear one, sometime the back plate light and sometime all the lights HS!

It first appeared on our first day when going to Brittany, after putting the light on when driving in a tunnel, I don't remember whether it was the first time or not. It lasted a pair of hours then after a few hundreds kms the screen was cleared I don't know how.
As long as I did not use the dimmed / head lights button, all was fine.
Another day back again and the day after without being cleared appearing immediately when I fired up.
The last day of our stay in Brittany, the sky being cloudy in the morning, car colour body being dark and passing through some forest, I kept the lights on the whole day: first the gremlin appeared then disappeared until the end on the day.
However on our way back the weather being chilly & cloudy, I kept the lights on the whole day too: nothing wrong happened even in the beginning, all was back as usual and the problem looks now being cured automatically again... so far.

Where could that come from?
A poor contact somewhere?
But don't tell me it might be moisture: the car was parked in the garage before our trip began and the first 5 days of the week were dry & shiny. Never the lights did that before but the last time several weeks ago when the left dimmed bulb was actually dead, which was normal.

COLVERT 20th May 2019 22:04

I had one of those little beasts. Turned out to be a poor contact in the plug to the light switch module. Unplugged it and sprayed the contacts with WD 40.-----Four years ago now and still working OK.----:D

Dorchester2 21st May 2019 07:17

Quote:

Originally Posted by COLVERT (Post 2735043)
I had one of those little beasts. Turned out to be a poor contact in the plug to the light switch module. Unplugged it and sprayed the contacts with WD 40.-----Four years ago now and still working OK.----:D

The difficulty is to know which...
And the PITA job to unplug & plug back all of them for there is very little room for my paws! I know that: I changed the four of them recently and I needed more than an hour to do the trick. From left to right when you're driving, the first one on the left (by that little window in the arch) and the third one on the right (bottle of steering liquid and A/C metal pipe) are awful. When I've a glance I can't do anything and when I introduce my big sausages I cannot see anything any longer! Unless I take off the bumper... but no time to spare if I do it and I already did it previously 2 or 3 times...
Hence I'll stand still, crossing fingers & the like that the gremlin is gone for ever as it did the two last days of our trip.
BTW I'm thinking that I might have been very close to you while going through western France from home to Brittany & back...

COLVERT 21st May 2019 10:31

The LSM ( Light switch module ) is inside the car. The switch you switch your lights on and off with.

Quite easy to remove and has only one plug.

There is info. in the How-To section of the forum on how to remove the module.

Dorchester2 21st May 2019 12:32

Quote:

Originally Posted by COLVERT (Post 2735121)
The LSM ( Light switch module ) is inside the car. The switch you switch your lights on and off with.

Quite easy to remove and has only one plug.

There is info. in the How-To section of the forum on how to remove the module.

Sorry I hadn't understood.
Easy to do as you say but I did it before as it was my first port of call.
It was as clean as new and then nevertheless it was given a few sprays of WD40.
And my wires under the bonnet are very clean and their sheath and contacts in very good condition as well without any trace of moisture.
Puzzling...

Dorchester2 22nd May 2019 07:27

Hello @COLVERT
Unless it may be an electronic gremlin on the printed circuit, I can't see any fault in my LSM...
Total mystery...
BTW I'd bought another LSM but I was told it should be 'adapted' with a T4...
Hence I couldn't swap them?
True or not? :confused:
Without a T4 would that disturb anything?
Thank you for your help.

N.B. I lighted on this morning, weather being a little foggy: no niggle at all, light on / off was fine. :confused:

COLVERT 22nd May 2019 10:26

Yes, it does need a T4 connection.---;)

pletevl 23rd May 2019 14:30

And these dodgy connections in the LSM have been known to cause fires ?


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