Headlight System Malfunction (2 Viewers)

[prharper]

Hit some trails yesterday. Halfway in, I got this alert on my dash. Says Headlight System Malfunction - Visit your Dealer. All lights work, low, hi and fogs. I checked the harness behind the grill that goes to the camera and radar. Anyone run into this before? It's a 2018 LC 200. Happy Fourth too!

 

[LBridges]

Not run into it, but Techstream should return a code that might help narrow it down. Perhaps the auto leveling thing got out of whack while bouncing along some trails.

EDIT - Per 2020 owner's manual: If the yellow symbol next to the 5K RPM spot is blinking, then it is something to do with the auto leveling system. If that light goes off after a few seconds indicates probably something else in headlight system.

 

[bloc]

16+ LCs have headlight leveling correct? Maybe all the bumps did something to one of the suspension position sensors?

 

[mcgaskins]

Did you do any water crossings or play in a mud field?

 

[Rigger]

^^This

My understanding is the 200 doesn’t play well with water.

 

[prharper]

Did you do any water crossings or play in a mud field?

Yes went through some mud and water holes. Thinking about it, may have come on around last water crossing. Maybe as high as fogs on Rhino bumper. Warning light, constant on and not flashing. Message doesn’t go away and really annoying.

 

[prharper]

I had to sort out an update issue with Techstream and got it to connect to the vehicle.
Fault is pointing to B241A Rear Height Control Sensor. I was able to get the exact timestamp of when it happened and then played back my dash cam recordings to correlate. I was crawling up a rock wall when the code was thrown and you can hear the alert come on the video. Truck never dragged or got caught on anything.

I tried clearing the DTC but it immediately throws the code again.

Where is this rear height control sensor located?

 

[mcgaskins]

I had to sort out an update issue with Techstream and got it to connect to the vehicle.
Fault is pointing to B241A Rear Height Control Sensor. I was able to get the exact timestamp of when it happened and then played back my dash cam recordings to correlate. I was crawling up a rock wall when the code was thrown and you can hear the alert come on the video. Truck never dragged or got caught on anything.

I tried clearing the DTC but it immediately throws the code again.

Where is this rear height control sensor located?

Hmm that doesn't make a lot of sense since there is no active height control in the Land Cruiser just the LX 570.

Yes went through some mud and water holes. Thinking about it, may have come on around last water crossing. Maybe as high as fogs on Rhino bumper. Warning light, constant on and not flashing. Message doesn’t go away and really annoying.

View attachment 2361241

My bet is the electronics got water logged during this crossing. It should have dried out and everything started working normally by now though. When I had a very similar issue, the truck was caked in mud from top to bottom, but after I thoroughly cleaned it and everything dried the issue went away by the next morning. Have you inspected all around the front of the truck to ensure there isn't water or mud trapped in there? There is less water protection for the front end with the Rhino bumper, so it's a little easier for water to make its way up into strange places.

 

[prharper]

Hmm that doesn't make a lot of sense since there is no active height control in the Land Cruiser just the LX 570.



My bet is the electronics got water logged during this crossing. It should have dried out and everything started working normally by now though. When I had a very similar issue, the truck was caked in mud from top to bottom, but after I thoroughly cleaned it and everything dried the issue went away by the next morning. Have you inspected all around the front of the truck to ensure there isn't water or mud trapped in there? There is less water protection for the front end with the Rhino bumper, so it's a little easier for water to make its way up into strange places.

I'm going to take it over to a car wash bay and get all the mud off and then bring back home and run an undercarriage sprayer.
Fault below is related to HL Autoleveling. On a different menu, it's referenced by rear height control sensor.

 

[mcgaskins]

I'm going to take it over to a car wash bay and get all the mud off and then bring back home and run an undercarriage sprayer.
Fault below is related to HL Autoleveling. On a different menu, it's referenced by rear height control sensor.

View attachment 2362983View attachment 2362984

The first step is definitely to thoroughly clean off all the mud and dirt and let it dry. I'm pretty confident that will take care of the issue as it did for me.

Could the height control sensor actually be related to headlight leveling, not suspension leveling? No 200 series Land Cruiser in the US ever got height control, but I wonder if this sensor is to control the headlight positioning. I have no idea how to read Techstream stuff, so someone else will have to chime in here.

 

[LBridges]

The first step is definitely to thoroughly clean off all the mud and dirt and let it dry. I'm pretty confident that will take care of the issue as it did for me.

Could the height control sensor actually be related to headlight leveling, not suspension leveling? No 200 series Land Cruiser in the US ever got height control, but I wonder if this sensor is to control the headlight positioning. I have no idea how to read Techstream stuff, so someone else will have to chime in here.

Your guess is correct. The sensor determines how to move the headlamps based on the sensor at the rear. Load the back end with a trailer, etc., and it should adjust headlight aiming. Pretty sure this came out at the same time as they went to LED headlamps.

 

[prharper]

Found a reference to the location of this thing.
Interesting note on suspension change causing it to trigger.

Gave the truck a good cleaning and will let it dry out some and check the connection harness later.

 

[RobW0]

I have a question for you. Is it possible that the Rhino bumper came in contact with the light assembly because of body flex and caused the height control sensor fault? How much space is there between the bumper and the light assembly?

 

[bloc]

I doubt a problem at the headlamp bucket itself would throw a height control sensor code. Much more likely a stick got shoved up into the rear suspension or something. Possibly even just a bad sensor.

 

[prharper]

I have a question for you. Is it possible that the Rhino bumper came in contact with the light assembly because of body flex and caused the height control sensor fault? How much space is there between the bumper and the light assembly?

There is ~ 3/4" gap. Also has rubber molding between the two.

 

[prharper]

Round two this AM. Took the height sensor control off to make sure it wasn't bent or water inside the connector. Here is the sensor before removal.

Here is the part below:

Put some lube on the steel slider harness (connected to frame) and the 3 retaining bolts to the frame. Installed. Everything seems to move freely and did not look like the mounting brackets were bent.


With more light, I was able to see the wiring connector did not look normal. Also could see where some metal near it was scraped.

Pre-removal below:

Reinstall and further inspection of the harness (removed some of the damaged loom):

Peeled back more loom and tape:

Ran Techstream with vehicle running and live scan. I can see sensor is getting power (4.99v and normal range is 4.75 to 5.25 v).
Had to quit working on it and get back to my real job.

I will get back under there this evening and repair the wiring harness. If that doesn't solve it, I'll test the connections of the sensor assembly per TIS. Last resort is to take it to Toyota dealer which I dread....

 

[prharper]

Problem solved!

There are three wires in the wiring harness to the sensor. The black one was sliced and the red and yellow were barely hanging together.
Removed sensor again, soldered wires together, sealed up, mounted and no more warning light or message to go visit the dealer.

Not sure what is more annoying but I would say visiting any of the 3 Toyota dealers in my area is worse. Don't think Toyota Care warranty would have covered it and they would probably try to charge me for a new Headlight leveling sensor < which I can't seem to find online anywhere for a LC but the ones for Camry and Prius are $400+.

I'm pretty sure the damage was from a rock based on the metal scrapes on the mount and one of the bolts. I didn't see any sticks on the rock wall trail even after looking at forward & reverse dash cam recordings.

Thanks for all the feedback and suggestions. Much appreciated.

 

[bloc]

Great tech!

 

[Jimmu]

I am having the same issue.

There was a crushed wire the same as PrHarper above.

Reconnected the cable but now its telling me there has been an initialization failure.

I cannot find the initialization procedure anywhere. Part of it is outlined in the above post.

Can someone point me in the right direction please?

Thanks

Jimmy

 

[prharper]

I've damaged the wire to the sensor on two occasions. However, I did not have to re-initialize or do anything in Techstream. Turned ignition on and dash error went away after wire repair.

Below is the init procedure.