High beams not turning off

[MightyMirageMpg]

Completely agree with fummins it's like you have two separate issues.

The 406 connector contains the ground for the relay coil so disconnecting it powering off the relay suggests the relay is functioning?

If it were my car this is what I would do, after disconnecting the battery

For the load side and dismount the relay box under the hood and pop the bottom cover off, see if something chewed up the wires in there or if theres a printed circuit board in there that the relays and stuff plug into make sure it's not delaminated or signs of carbon tracing, black spots etc

If you want to look at the control side of things, ide disconnect c407 which looks to be the main plug in for the etacs ECU too the junction box and look at it. This actually seems like the most likely culprit right now except for the fact the lights stay on with the relay pulled

You could also disconnect c10 which is the data connector from the switch too the etacs ECU and see if the light goes off.

Fummins makes a good point that resetting the system makes a change, but I would personally start on the load side just because it's easier to understand and access.

[AyAyron]

Thanks for the step-by-step process Mighty, will try and report back. I doubt I have the tools to dismount the box but let me see what I can do.

[AyAyron]

Hey Mighty, I have a RHD and the C10 in the diagram seems to be in the steering column. Is this where I should look for it? So far the other locations have been the same: i.e. junction box and kick box on the left hand side (in my case, passenger seat)

[MightyMirageMpg]

Ya I wouldn't dig for that. It was a way to see if the switch was commanding the light to go on. Possibly a fuse you could pull to get the same result. Still doesn't explain the relay thing which seems rather... odd..

There's got to be a way to get into the computer and read the command values. I don't know how to though hopefully someone smarter will chime in and teach us both.

[daleWV]

In post #6 of this thread the OP stated that one of the aftermarket additions that came with the car was "led strips parking lights".
Barring the possibility that some wires have rubbed through and shorted together somewhere, I would be highly suspicious that these "led strips parking lights" could somehow be involved with the high beams being on even when the high beam relay is pulled. Just saying.

[7milesout]

... Just saying.

For a friend?

[Fummins]

In post #6 of this thread the OP stated that one of the aftermarket additions that came with the car was "led strips parking lights".
Barring the possibility that some wires have rubbed through and shorted together somewhere, I would be highly suspicious that these "led strips parking lights" could somehow be involved with the high beams being on even when the high beam relay is pulled. Just saying.

Reading is hard.

[AyAyron]

In post #6 of this thread the OP stated that one of the aftermarket additions that came with the car was "led strips parking lights".
Barring the possibility that some wires have rubbed through and shorted together somewhere, I would be highly suspicious that these "led strips parking lights" could somehow be involved with the high beams being on even when the high beam relay is pulled. Just saying.

Hey, the led strip parking lights are directly connected to the wiring to the stock parking lights via a splice in the parking light supply wire.

To Fummins: the fuse picker snapped on first try I used a small flat head screwdriver to pry them out. The fuses do NOT turn off the high beams (just like the relay).

Quick update: I went to a mechanic who reset the codes. Now my SRS light is permanently on (better than having high beams on haha). I am going to try someone else this week who has agreed to look at the wiring for me.

[AyAyron]

Final update: Sorry about the super late update, got swamped at work.

I ended up going to an electrician mechanic who checked everything. It seems it was some freak accident because all he did was use a forced air machine to clean the engine bay fuse box and remove the SRS error code (something about front bumper RHS sensor). At the time of checking it the high beams were not forced on (problem did not return after the code reset last as per last update).

He did check the wiring for me and its fine: both the relay and fuse worked after the cleaning and the control side had no issues either.

For now all's well and the car has been running fine.

[AyAyron]

Final final update: re-opening this thread because the issue came back,

I finally diagnosed the issue with the car electrician after 3 visits in the last week: its the windshield wiper assembly gone bad. Most likely circuit corrosion. We bought a new one from the local used parts market and the issue is gone.

Also found out this is a common problem with the Mirage 2012-14 model in humid climates and usually both the windshield wiper assembly and the headlight assembly need to be replaced. Basically there's a plug that goes into the wiper assembly in the steering column that holds the wiring for both the wipers and the headlights. It has a circuit inside (the headlight one does not have such a circuit).

Just restating the problem: Its NOT the high beam being forced on, but the dimmer/passing switch which turns on both high and low. This is why when I pulled individual relays the lights would stay on (I was unable to identify the high vs low change during this process).