Hi there,
I just wanted to clear up some confusion I have over a DRL switchback kit I have bought. After reading many forum posts about others retrofitting, I couldn’t seem to find the exact answer I was looking for, so apologies if it has already been asked/answered!
I have bought the following switchback led kit and a 5-pin changeover relay (as most prefer them over the drl modules!). My confusion is with the wiring of the relay with the different wires. There is a red (live), black (ground) and a white wire with a connector (I’m assuming to connect them both together?) coming from both the bulbs. There is then a main live wire which I’m guessing goes to the relay.
Just so I’m not going in circles my questions are:
- Pin 87a for the live wire from the bulbs
- To get the DRL’s to turn off when dipped beams go on, a wire needs to tapped from the sidelight fuse to pin 85 on the relay.
- Pin 86 is for ground
- Pin 30 for another tapped fuse to turn the led’s on once the ignition is on.
- Dumb question I’m sure (I’m not an electrician!), but once dipped beams are turned on, the indicators will still work? Correct?
Again, many many thanks for any help!
Three wire switchbacks are all generally the same wiring.
You should NOT need any relay
Black wire is common earth
White wire is side light positive
red wire is indicator positive.
The side light is live all the time if using as a drl
The switchback bulb shuts off the sidelight/drl when it sees indicator voltage and flashes orange.
a second or two after the indicator voltage is removed - the switchback bulb reverts to sidelight/drl
I was hoping to wire it all up so that I wouldn’t need to remember to turn on the sidelights every time I get in the car.
eg. Start car and they turn on automatically. When dipped beams are needed and switched on, drl’s are off and are just like regular indicators.
Sorry for any confusion!
Would be easier to have the drl on all the time using an ignition live.
Then when you switch on side lights - you have side + drl together
When you switch on dip beam - you have side + drl + dip
At any point - if the indicators were used - they over ride the drl part of the switchback.
I was reading in other forums that the drl has to switch off for MOT purposes when the dipped beams are turned on?
Is that the case?
My MK3 Leon has the drl on all the time - even with the headlight on.
The drl becomes the indicator when used.
Never had any mot issues and i’m pretty sure that SEAT will have complied with the regs.
The MOT manual says :
Front and rear position lamps
Vehicles must have 2 front and 2 rear position lamps, except for tricycles or quadricycles that are less than 1,300mm wide.
Daytime running lamps (DRLs) or headlamps may function as front position lamps. If the DRLs function as front position lamps, they may or may not dim when rear position lamps are switched on and may dim or turn off when headlamps are switched on.
So from reading your comment and the MOT manual, my understanding is that the drl is allowed to remain on when the sidelights, dipped and high beams are on?
I’d like to not have any unnecessary failed MOT’s/traffic stops (I’m a rather young MX5 owner! 
)
It is common place now to have drl on with headlights. I can’t see you having any issues.
Unless you have an NC1 - your only issue then could be the orange filters in the headlights.
Having orange drl’s could get you the wrong sort of attention.
I have an NC2, so I should be all good.
Many thanks for your help!
My understanding is that DRL’s are required to dim or extinguish when headlights are deployed and that the cheap and cheerful dimming modules are just that, and after failing , were replaced with “turn off the DRL’s when the headlights are on” relays.
6K non E marked bulbs …?
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