Lotus Elan

Grounding issue?

PostPost by: phil1800 » Sun Sep 19, 2021 12:56 pm

My 67 S3 DHC has developed an electrical issue on a short trip around town. The rev. counter stopped working, as well as the main front lights. Also, both the fan, wiper and blower stopped working, as well as instrument lights. Seems to be a dash grounding issue, but what puzzles me that the interior light is still working, as well as the front parking lights, rear lights and flashers. The visible grounding points (behind the ash tray and near the handbrake are all good. The loom is almost new and worked well during the last 4 years. Any ideas where to look before I start dismantling the dash?
Thanks for your input!

Philipp
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PostPost by: oldelanman » Sun Sep 19, 2021 4:06 pm

Have you checked the fuses ?
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PostPost by: phil1800 » Tue Sep 21, 2021 4:16 pm

I have checked both!! fuses. Is there a readable loom layout available? The one in my manual is not. I suspect this to be an earting issue, so readable digram of the earth wires would be very helpful.

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PostPost by: Mazzini » Tue Sep 21, 2021 4:53 pm

Check the earth on the front right hand radiator bracket.
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PostPost by: RichardS » Wed Sep 22, 2021 4:56 pm

image.jpg and
Phillip
I had a similar symptoms when the green 12v feed wire to the dash became disconnected. I have connector blocks and one of the blocks had become disconnected so easily sorted by pushing the blocks back together. S4 wiring is not quite the same but looking at the S3 wiring diagram the dash is fed by a green wire from the fuse box. So it maybe that there is a break in the green wire somewhere. A multimeter or auto test probe would help you trace the problem and check you have continuity to earth.
I have an S3 wiring diagram but it is very small but photo looks readable
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PostPost by: Slowtus » Wed Sep 22, 2021 5:03 pm

Does this have a an ammeter (memory says yes, but it has been a while...) check those FIRST because that will give you the symptoms you describe.
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PostPost by: phil1800 » Sat Sep 25, 2021 4:58 pm

Richard and all,

Problem solved. It was indeed no grounding issue, but a bad connection in the green feed wire. While at it, I relocated the blinker and headlight relays the shop installed on the handbrake tree. I fabricated a thin, stainless bracket, utilizing a dashboard screw as attachment point. The Elan was put back in service for shopping at the garden center with daughter Lola.
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PostPost by: Mazzini » Sat Sep 25, 2021 9:20 pm

Excellent!!!
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PostPost by: TBG » Sat Sep 25, 2021 9:36 pm

S3s are the bees knees.........................D
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PostPost by: RichardS » Sun Sep 26, 2021 9:56 pm

Pleased I managed to point you in the right direction!
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