texascayenne

Howdy everyone,

My wife and I recently bought a 2017 Cayenne GTS. We love the car and have been enjoying it, but the Lane Change Assist has not been working. If the LCA button on the armrest is pressed, a warning saying service required will pop up on the dash. The dealer replaced both of the rear sensors for the LCA, but still no dice. Maybe they didn't recalibrate it or some other issue, not sure. However, I've noticed that the LCA lights on the mirrors will flash with the turn signals. Is this normal operation, or did a previous owner reprogram the lights to flash with the turn signals? I did a brief search but couldn't find anything about it. Let me know if you have any insight! Thanks.

Needsdecaf

The LCA lights should not flash with the turn signals. Nor is there a way to reprogram this that I am aware of. You're talking about the light that's in the base of the mirror housing facing the driver?

KBell

Went through something similar as you.
LCA module in rear bumper died.
New module and ½ hour of doppler calibrating.
The fancy doppler machine recalibrates the sensors.

I would call dealership and say, "Hey, how can we rectify the LCA?"
That is why you brought it to them the first time.

Maybe it needs recalibrating? Just shooting in the dark.

Good luck. Keep us up to date.

texascayenne

Ohhhhh I was misunderstanding the lights. So, there are lights on my mirrors that light up with turn signals on the far side of the mirrors, but I didn't realize that the LCA lights were in a different spot on the inside of the mirrors (because I've never seen them light up!). I just went and adjust the brightness settings to test, and the passenger side is working, but the driver's side is not! So it's an issue with the light on the driver's side that's causing the system issue.

twodollardoug

I have a similar but different LCA problem with my 2012 CTT. If I use my key to the car the LCA doesn't work. But if I use my wifes key it does. So I will be watching this thread.

jl-c

you can turn it on and off in CAR. OPTIONS so twodollardoug I suggest that is your issue. It is not activated for your key.
As far as OP is concerned, throw it back at the dealer. "It doesn't work, you've failed to fix it now do it properly!"

waterpanda

Could be related, sharing my story.

Bought my 2016 Cayenne GTS in early 2022. LCA worked but it was displaying the same error. I also noticed a strange behavior, LCA would work at night but not during the day... Weird.

Then I had all my door switches & electronics die one day. Turns out there's a leak in the connector grommet causing all the pins to corrode over time and lose connection. Replaced all the male pins on the car-side after sourcing hardware from eBay, the door-side still was lightly corroded, didn't warrant replacing entirely. I cleaned them up to the best of my abilities (really tight space) and reconnected everything, then voila door switches came back and LCA became fully functioning, even during day time.

My guess is LCA lights are brighter during day-time, therefore pulling more power. Corrosion in the connection caused higher resistance previously, tripping the error in the module.

For future sakes, I want to replace the driver-side harness entirely, since I'm not fully at peace with the remaining corrosion in the driver-side connector. But am having trouble finding & sourcing the door-side wiring harness matching my specific configuration - maybe I need to call the dealer.

UNYboater

To expand on this reply, LCA may be optional for each driver (one set of settings per key or memory button on driver's door, I believe). For example, on our 2011 TT my wife loves ACC but I'm not a fan so I can have it disabled with my key but enabled for hers. That extends to a lot of things on these cars; they are incredibly customizable per user/driver.

twodollardoug

That was the first thing I checked.

porsches4ed

I had the same issue with my 2015 e-hybrid. I took the rear bumper off (very easy), and checked the sensors. The lights work in the mirrors and the brightness can be adjusted.





















Bought a pair of used ones and took it to the dealer to have it programmed and it doesn’t work. The dealer says it shows no communication with slave sensor (drivers side). I checked the wire harness and all the wires for corrosion, cuts or kinks. Everything was fine. The Porsche tech told me it has to be the module under the dash. He said those rarely go out and it’s extremely expensive. The tech told me to check pin 5 because that’s the communication wire. It looks fine no damage. He said another option would be to run a new wire from pin 5 to the module under the front dash.

I will check it with my spare key to see if it starts working. I don’t have pp

porsches4ed

Spare key didn’t fix it.




I was just going to buy an aftermarket kit and use their sensors the tap into the oem lights with the wires the kit comes with or just use their mirrors with the blue dimmed / heated mirrors.

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porsches4ed

ok I fixed it! It’s the windshield light and rain sensor it was disconnected. I added auto a dimming mirror. Once I connected it now everything works.

evilcorgi

Hi, I’m experiencing something similar. “Lane Change Assist currently not available”. Sure enough, my automatic wiper and auto headlights don’t work (if I put it in auto, it’s always on). I am guessing it maybe the same issue. I disassembled the dome light and the mirror, but I don’t see any connectors disconnected. Could you point me to which connector it was?