HID Headlight Leveling System fault

First a bit of history: About a year ago, I received the headlight leveling system warnings comprising a red triangle alert with exclamation point in the middle located on the dash, combined with a yellow(ish) warning symbol on the center stack display comprising what looks like a headlight with up and down pointing arrows. Eventually, the warning lights went out, but the HID headlamps were left pointing in a down position that lit barely 10 ft in front of the car.. This is is supposedly their default position when the sensor breaks, most commonly due to moisture entering the sensor innards resulting in corrosion of the contact points. I effected the repair quoted elsewhere on this forum, and it was good to go.

Today, Ive got the warning lamps back (pics attached).. But what's different is that the headlights appear to be aimed as they have been since it was fixed a year ago.. Im not experiencing that down position that so typically accompanies a bum sensor. So, Im in a bit of a quandary as to what to do. Taking it to the dealer will likely result in him replacing the sensor, which, with labor, is easily a $500 job.. And since the lights seem to be working as well as they have over the last year, I feel something else besides inner corrosion of the sensor, as happened last time, may be causing this.

Does anybody know what else can happen to this system that will trigger these warning lights? I went under the car and examined the plastic 'dog bone' and surrounding parts that allow the sensor to move so as to establish 'level' and it looked ok on initial review. Could a calibration fault not related to sensor failure trigger the warnings? Anything else?

Thanks for your thoughts.

 

Last time, I just had to clean up a little rust on 2 of the springs, and contact was reestablished. I siliconed the gasket and applied dielectric grease, and sealed it up. The salient point is that then, prior to the 'fix', the headlights were aiming sharply down in front. Now, however, the headlights seem to be fine, ie, no change when the warnings came on. So, Im trying to figure out what else could trigger this fault.

BTW, regarding the scantool you mention, I have my own obd2 code reader, and the fact is, these scantools read and clear faults stored in the ECU related to engine function.. My ecu showed no codes stored. Perhaps the scangauge2 can read the CAN bus where perhaps the fault code might be stored, or, perhaps its a 'pending' code that my tool didnt pick up.. I dont know, but I dont want to get too far afield. Short of having a shop or the dealer going on a wild goose chase looking for the cause of this, replacing sensors along the way which may or may not need replacing, Im looking for possible reasons as to why the alert would trigger without the headlights shifting to their default low-aim position indicative of a sensor not able to do its job.

 

So there's an ECU dedicated to the leveling system.. I dont have a code reader for that, unfortunately; just the main engine ECU. How do you read the fault codes stored in it?

 

So, do you think this problem, then, would most likely require a sensor replacement? Im just surprised the headlights seem to be behaving as they did before the dash warnings were triggered.. Maybe in time, they will go into their low aim position usually associated with a faulty sensor. If I knew it was the sensor, I could order a replacement and save about a third of the cost, on the sensor, and I could save dealer labor charges.