Boykie

Info exchanged, looks like correct part was sourced. OP will update us on any progress here (I hope).

Tonyls600h

Thanks for all the info, yes will definitely update when I have a resolution.

mikegoblan

I'm running into the same issue، hit a dearlight, front passenger side headlight replaced, getting the C1A6A error code and the dealership wants to charge me 20k to replace the pre-crash ECU and other systems. Even though everything worked fine before replacing the headlight, now my LKA and auto high beam don't work at night, but LKA works fine during the day.

any thoughts/ ideas ?

swfla

iTrader: (1)

Your question isn't clear to me. What's your issue? Don't trust dealer diagnosis? Price too high?

Anfanger

Did you replace the headlight with exactly the same part number? Was it used or new? This particular error code requires extensive testing using Techstream (active tests) and a multimeter. But solution to majority of issues, according to the manual, is to replace the headlight or the recognition ECU. I suspect, there is something wrong with the IR filter otherwise LKA wouldn't work at all.

Boykie

I 90% know what this is and it isn't pretty. Let me guess - 10-12 year? It's the headlight. It's not exactly wrong, more of a .... mismatch.

Tonyls600h

Hi after much head scratching from two lexus dealers it appears the new headlight assemblies are supplied without a crutial part i.e. a halogen bulb inside the headlight. Remove the large grey coloured cap on the back of the headlight and see if there is a wire with plug attached hanging loose and a hole for a halogen bulb to go. Is so this could be the cause of the code. Every body assumed the unit was complete but it isn't. Check this and see.

Boykie

Uuuum no...

mikegoblan

my issue is the same exact issue that the original post author ran into. Same error code, just trying to see how he resolved it.

And yeah, I do not trust the dealer diagnosis they charged me 2 grand just to tell me I need to replace the entire system for 20 grand.

mikegoblan

thank you kind sir, Ill check that today and post.my findings.

and the headlight was ordered using my VIN number through the dealership, brand new, cost over 4k. At first they said it was the wrong part but confirmed it has the IR thingy and I tested it using techstream.

Boykie

Yeap yeap, what year is it?

Tonyls600h

Just rotate the cap anticlockwise to release it and prize it off. Once a halogen bulb installed everything worked as it should and no code.

mikegoblan

2013 LS460L with Adaptive Cruise Control, Lane Keep Assist.

Boykie

Ok, check bulbs as Tony suggested first. But thing is there was this subtle headlight engineering design change that is not reflected in manuals properly but which directly affects c1a6a.
Also - was JUST the headlight replaced? I mean no harness repair or replacement? Any aux parts?