DRL Install Noob - Which Wire?

[rs_nz]

Hi All,

Im attempting to install my new DRL's myself. 90% done, but unsure where to tap the last wire into?

First pic is straight off the batt so I know they work.

Install Diagram has the last wire "White - To Headlight +12v"
Pic #2 of the LH headlight connection.. Is this where I should be tapping into? if yes which one?

[DV52]

^^^^ hmm........... I don't have a wiring diagram for a Polo 6C, but I'm not sure that it's as easy - sorry!! If my suspicion is correct (and I hope that it is not) then the following test won't work.


By definition, DRLs are switched-on when the headlights are turned-off: so get yourself a multimeter and with the light switch in the off position (but ignition switched-on), test the individual pins on the headlight connector. If any of these pins measures 12 Volt - then it's a candidate wire for the DRL.

However, my expectation is that you won't find any of the pins have 12 Volts with the configuration that I describe above because I suspect that the wiring loom won't contain the DRL wire.

Not sure if you are aware, but the control module in the Polo 6C that manages the car's exterior lighting (it's called the Body Control Module, or BCM) shares many features to the Golf Mk7 and all MQB platform vehicles. The exterior lights are NOT supplied in the traditional way with a fuse via a relay from the battery. Instead, the individual lamps are supplied directly from the BCM (no fuses because the BCM provides protection and monitoring functions for each individual lamp).

Each of the 35 exterior lamps in the car has it's own set of programmable "adaptation channels", called a Leuchte-set, which controls a specific pin on the BCM. This BCM pin is then wired to the lamp connector like the one shown in your second picture. So the lamps need to be "programmed" to energize the DRL function if this is not done from the factory. Programming is done via a diagnostic cable like VCDS, or OBDeleven.

So - as I say, I don't have a wiring diagram for a Polo 6C), so what I'm saying above is a quess. But if I'm correct, then you have two options (IMO): First - you could run two new wires to the BCM pins and then program the Leuchte-sets for DRL operation.
Second- you could operate the DRL from a new relay (which you will need to install). This relay would be wired so that the normally-closed contact supplies the DRL when the headlights aren't energised. Note: the 12Volts to the relay contact needs to be a "Terminal 15" supply - which means that it must only be live when the ignition is switched-on. You should be able to find a siutable T15 supply on the fusebox - since the LEDs won't draw too much electrical current, the additional load shouldn't be a problem for the fuse size.

To get the proper operation, the trigger wire to the new relay will need to be connected to either the Parking light, or the low-beam light.

See the diagram below

Don