Sunday 3 November 2013

Aux Panel rewiring - dimming Savage switches

Re working the Aux panel wiring to both install the radio and fully setup the Savage switches so they glow on dip beam. The switches are double pole double throw - one side is used to switch the LED between full 12v and via a 5k resistor from the sidelights circuit.

I picked up the circuit from www.locostbuilders.co.uk, redrawn/coloured for my setup/cable colours. Each switch has its own resistor and separate led feeds from the device itself which should eliminate impact to the cars existing circuits.

This wiring means the lighting indicates when the switch is depressed, not necessarily that the circuit it operates is functioning (there is always a tradeoff)

Key: C - common, NO - normally open, NC - normally closed:

I tried 1k ohm resistors and 5k ohm resistors - the latter used here (but not great pictures) showing the  dim lit state on the left and with the fog lamp depressed on the right - showing brighter when its on: 

The wiring took an age & this is as tidy as I can get it. I'm not using standard automotive colours due to using up some cable I already had but roughly the scheme is:

Red - +ve ignition or permanent (the radio takes a permanent feed to remember stations)
Black - ground
Blue - lights +ve feed
Yellow - device out

All blacks terminated to the casing with a rivnut, and the +ve lines via a chock block:

Losing the light too much to take the dash off and adjust the aux feeder circuit; so the last job today was drilling the M3 cap head speaker bolts & pulling through the speaker cable from the dash area, through the tunnel & up into the boot space:


Post note:
On testing I realised my fog switch illumination was not a true tel-tale - it was wired to the side-lights for its dim and full brightness.

Update - re worked the switches and preferred switch dimming circuit later to ensure the fog lamp is a true tel-tale & standardise the switch wiring.

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