Headlight Range Control Defective Warning Light Help

[4point2S5B8]

Hello everyone,

I’m in need of a little help.

My vehicle:
Audi S5 B8 AT V8

Here’s the backstory. Bought it a couple of months ago to keep miles of our other vehicles. After a few weeks, I got to drive it a night and noticed my headlights pointing at the ground. I was about to put a screwdriver to the back of the headlight and as I learnt more about my car, I learned that the initial level is originated by a sensor at the back driver side.

I had purchased a month worth of Carista but I didn’t see it working for my needs. So I went with OBDEleven but before I tried to level the headlights with it, I decided to look at the condition of the sensor itself FIRST (even though I had NO headlight related warning light on my dash.)
During my inspection I found the link that connects the suspension and the arm of the sensor had broken off.

So I replaced it (not a fun job at all) and put it back together. The moment I turned on the ignition, I got the Headlight Range Control Defective light. I was like “ok! I got this!”, I connected the OBD11 and scanned. Two faults showed up, so the plan was to clear them and level the headlights. I cleared the codes but came back seconds later but on a lighter note (no pun intended) my headlights leveled once the code cleared the first time. I tried to level them to see if that would help clearing the code but that didn’t work.

But upon looking closer at the codes one read that it was voltage supply related, so I am thinking the sensor may need to be coded? Or is it something else?

On a last ditch attempt (before I replaced the new sensor with ANOTHER new sensor) I put the old one in to see if the code would clear but no luck. So I installed the new replacement to the new replacement and I still got a warning light. BTW, I purchased the sensors from Amazon.

All help is greatly appreciated!

[Smac770]

The sensor, assuming you do not have the 1BL adaptive suspension, is just a basic voltage divider. 5v on one pin, ground on one pin, and the output voltage based on the arm angle on one pin. So you could start by unplugging the plug from the sensor and making sure you can measure 5v and ground on two of the pins. Then plug it back up and backprobe the remaining pin to see the voltage vary as you move the arm up and down. The DTC implies that either it's seeing excess current flow on the 5v line out from the control module or is seeing always ground on the output line from the sensor (ie, 5v is grounded, so the voltage divider is between 0v and 0v, so the output is always 0v).

So you probably have a wiring issue. But to confirm the wiring, you'd have to pull the plug on the J431 range control module, which is behind the glove box. On the 26-pin plug on the J431, pin 11 is brown wire to pin 1 on the G76 level sensor, pin 10 is yellow wire to pin 2 on the G76, and pin 7 is gray/blue wire to pin 4 on the G76. So I'd disconnect both plugs and confirm the wiring tests for continuity and no shorting to ground or 12v for all three wires.

[4point2S5B8]

The sensor, assuming you do not have the 1BL adaptive suspension, is just a basic voltage divider. 5v on one pin, ground on one pin, and the output voltage based on the arm angle on one pin. So you could start by unplugging the plug from the sensor and making sure you can measure 5v and ground on two of the pins. Then plug it back up and backprobe the remaining pin to see the voltage vary as you move the arm up and down. The DTC implies that either it's seeing excess current flow on the 5v line out from the control module or is seeing always ground on the output line from the sensor (ie, 5v is grounded, so the voltage divider is between 0v and 0v, so the output is always 0v).

So you probably have a wiring issue. But to confirm the wiring, you'd have to pull the plug on the J431 range control module, which is behind the glove box. On the 26-pin plug on the J431, pin 11 is brown wire to pin 1 on the G76 level sensor, pin 10 is yellow wire to pin 2 on the G76, and pin 7 is gray/blue wire to pin 4 on the G76. So I'd disconnect both plugs and confirm the wiring tests for continuity and no shorting to ground or 12v for all three wires.

Before I start testing, are we certain the sensor doesn’t need coding/adaptation?

[Smac770]

The sensor is not on the CAN bus, so you can't do anything with it in that regard. You can, and should, perform a basic setting of the headlight range control if you've changed something in regards to that system. That's what your 01539 is talking about. But your 01537 is an electrical fault, not a programming fault. If you have OBDeleven Pro, then you can access basic settings, and it should be fine to attempt performing the operation to see if it can complete and if your errors go away. I would not expect that result, but it's painless to try (unless you only have OBDeleven basic).