gotcha . .
maybe look at something like this. (not tried it myself, but i think it will work)
break off the -0ve/negs for the two lights you want to "duel-use" . . . . . and run them through a relay.
the relay will have
COM-(comon)
NO-(normaly open)
NC-(normaly closed)
then the coil contacts +ve & - ve
**
run the light negs via the relay to switch between the common grouns with the other 4x lights and a new 0ve chassis ground.
you will need a second switch, use this to power the relay 12v on/off.
Note: if you use the same +12v that feeds the lights for the relay its timed!! so will switch off after the timer.
take if from a 24/7 +12v supply or even better a leisure battery . . .
***************************************************************************************
Factory Non-LED 3 wire setup:
(brown) - earth point left a-pilar
(brown/red) - connection 1 main harness (BCM switched neg 0v)
(red/black) - positive connection 1 main harness (BCM timed +12v) ( 7.5A fuse 24 holder C)
****************************************************************************************
Factory LED 2 wire setup:
(brown/red) - connection 1 main harness (BCM switched neg)
(red/black) - positive connection 1 main harness (BCM timed +12v)( 7.5A fuse 19 holder C)
****************************************************************************************
...
have a look at these relay options . . .
Gebildet JD1914 12V 40A Car Relay with Harness Sockets, 5 Pin SPDT Relay with Color-labeled Wires for Automotive Truck Van Motorcycle Boat (Pack of 2): Amazon.co.uk: Automotive
amzn.to
.
MICTUNING Relay Switch Harness,12V Fuse Relay Harness Set-30A ATO/ATC Blade Fuse,5-Pin SPST Automotive Electrical Relays with Heavy Duty 14 AWG Wires-6 Pack : Amazon.co.uk: Automotive
amzn.to
..
Shop Taiss/DC 12V Coil Electromagnetic Power Relay 10A 2DPT 8 Pins 2NO+2NC LY2NJ with YJTF08A-E Socket Base (Quality Assurance for 2 Years) YJ2N-LY. Free delivery on eligible orders of £20 or more.
amzn.to
.
Shop DC 12V 1-Channel Bistable Low Level Trigger Module Relay Soft Touch Switch. Free delivery on eligible orders of £20 or more.
amzn.to
.
and a 12v switch like any of these . .
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