Dipped Lights not working
Dipped Lights not working
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Random24234

Original Poster:

101 posts

171 months

Sunday 2nd November 2014
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A couple of weeks ago I was parking the cerb in the garage flicked on the dipped beams, and nothing. The usual symptoms were present, full beams work perfectly, side lights worked as well as they ever did. Frustrating as this was i figured, well this is something i probably can fix.

So the next weekend I examined the bulbs, got the old voltmeter out and discovered, no voltage across the terminals which was puzzling to me. Double checked using the ground from the side lights which I had took the opportunity to replace the connectors and bulbs for leds so they now work perfectly displaying a nice white light, still no voltage on the main beams though. Back to the forums and it seemed everyone is pointing to the controller boxes.

Its not clear but there is in fact three boxes on top the fuel tank that deal with lights, the Light control box, the dim dip control box and the dim dip box. Now i implore anyone who knows better to correct me. Ignoring the dim dip function full dipped beam works like this :- there is a red yellow wire from the the light control box that goes into to the dim dip box, if the appropriate signal is also sent from the light control box to the dim dip box it will output the red yellow as a blue yellow, which is then fed into a splitter i can't find that then goes to the connector behind the helmet holder as two leads left and right blue/yellow that goes to the nose connector hidden in the passenger footwell that then goes to the light wells in the front.

My problem is i have a nice healthy (as much as i could expect tbh from TVR grounding) engine off voltage of 12.5 volts out of the dim dip box on the blue/yellow wire when the dipped lights are on, its still there on the junction connector behind the helmet holder, and i can't see any reason it would not be there by the connector in the footwell though i did not get a chance to test that as it was getting dark yesterday. Rain having interfered with my plans to look further today, i was wondering does anyone have any suggestions? I will check the footwell, but i do not expect to find a issue there, which leads me to wonder is there a connector like there was for the sides somewhere in the cavity in the wheel well i missed for the dipped?

Boatbuoy

1,972 posts

185 months

Sunday 2nd November 2014
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My first point of call would be the connectors on the black boxes on top of the fuel tank in the boot. I've had two issues with mine that have lead to partial headlight failure. The connecters seem to arc causing the contacts to blacken or burn out!





Hope that helps.

Olly

Random24234

Original Poster:

101 posts

171 months

Monday 3rd November 2014
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Sadly, i have checked all three boxes and they all seem healthy with the right voltages. Any other suggestions?

Tarmacshredder

135 posts

153 months

Monday 3rd November 2014
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My problem with dipped beam was the control boxes, burnt connectors and burnt out tracks on the board. Was there any smell in boot of burning plastic? I would pop the covers off the boxes and visually checkboxes boards for damage. Worth swapping out the fuses as well just to make sure it's not ad simple as that.