Car in Question: 2017 NAR VW Jetta SEL (BCM PQ25 Max3 7E0937190)
End Goal of project: To wire a SPST switch to control DRLs. If it works, maybe even use more SPST switches to control other functionality.
Description of current problem: I read up about relay 173 (controls DRLs) in older cars but according to erWin that relay isn't in use since July 2016. So I'm trying to find the output wire from the BCM that controls the DRL. To do this, I downloaded the Wiring Diagram from erWin using my VIN but it is 999 pages long and I (with no experience doing any of this) am struggling to find the info I need.
Using erWin's iWire online utility seems helpful as I found the pin-out for my rotary light switch which then lead me to find that the BCM/Vehicle-Electrical-System-Control-Module is labeled in the diagrams as J519
But how do I find the pin for the DRLs?
https://imgur.com/a/UrlRekE
----------More info on project below----------------
Project Justification: Multiple secure area checkpoints in sequence, cannot have any lights on. Holding the handbrake slightly is even more suspicious according to security personnel.
Why not turn off with VCDS? Because I would prefer to have an on-demand DRL switch. Since DRL is BCM controlled, using VCDS would require me carry a laptop, plug in and then turn off DRL. Also, I prefer to have DRLs during normal driving so disabling them permanently is not an option for me.
More benefits of having DRL switch: Can use easily in drive-in cinema, drive through Christmas lights parks, reaching a dark-sky village for star gazing etc.
Other thoughts: DRLs turn off when handbrake is pulled, maybe I can wire in a switch that gives a constant to the wire to fool the BCM to think handbrake is pulled and turn off DRLs but again this would mean that the warning "Release parking brake!" would annoy the driver
End Goal of project: To wire a SPST switch to control DRLs. If it works, maybe even use more SPST switches to control other functionality.
Description of current problem: I read up about relay 173 (controls DRLs) in older cars but according to erWin that relay isn't in use since July 2016. So I'm trying to find the output wire from the BCM that controls the DRL. To do this, I downloaded the Wiring Diagram from erWin using my VIN but it is 999 pages long and I (with no experience doing any of this) am struggling to find the info I need.
Using erWin's iWire online utility seems helpful as I found the pin-out for my rotary light switch which then lead me to find that the BCM/Vehicle-Electrical-System-Control-Module is labeled in the diagrams as J519
But how do I find the pin for the DRLs?
https://imgur.com/a/UrlRekE
----------More info on project below----------------
Project Justification: Multiple secure area checkpoints in sequence, cannot have any lights on. Holding the handbrake slightly is even more suspicious according to security personnel.
Why not turn off with VCDS? Because I would prefer to have an on-demand DRL switch. Since DRL is BCM controlled, using VCDS would require me carry a laptop, plug in and then turn off DRL. Also, I prefer to have DRLs during normal driving so disabling them permanently is not an option for me.
More benefits of having DRL switch: Can use easily in drive-in cinema, drive through Christmas lights parks, reaching a dark-sky village for star gazing etc.
Other thoughts: DRLs turn off when handbrake is pulled, maybe I can wire in a switch that gives a constant to the wire to fool the BCM to think handbrake is pulled and turn off DRLs but again this would mean that the warning "Release parking brake!" would annoy the driver
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