DIY Smartphone Scan Gauge - OBD Fusion (1 Viewer)

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Yeah KCLV is somewhere in the 14-18 range IIRC when I was watching it before. I’ve just never quite understood the actual impact.

It's a global correction factor for timing advance. Historically, Toyota engines will start with a baseline correction around 15 KCLV. It will very slowly walk that value upwards as a timing advance factor, inching closer to the knock threshold. It's a longer term variable used optimize power and fuel efficiency, while compensating for engine health, environmental conditions, and/or fuel quality. It'll creep upwards very slowly but will retract quickly with any sign of knock. It's part of why they say not to switch between octanes regularly as the engine has to re-learn to take advantage of more octane, or will experience knock when going back to a lower octane.

Towing is some of the most stressful use cases for an engine as it operates at high outputs for extended periods, with lots of heat saturation. It's where octane makes the most difference, and can be beneficial to cover for other factors.

Not saying it will definitely make a difference and will depend, but you might entertain some simple maintenance - clean the throttle body and use Seafoam through the intake track and fuel system. This can often wake up an engine and has shown to have benefits to KCLV. You might be able to get some performance back with 87.
 
It's a global correction factor for timing advance. Historically, Toyota engines will start with a baseline correction around 15 KCLV. It will very slowly walk that value upwards as a timing advance factor, inching closer to the knock threshold. It's a longer term variable used optimize power and fuel efficiency, while compensating for engine health, environmental conditions, and/or fuel quality. It'll creep upwards very slowly but will retract quickly with any sign of knock. It's part of why they say not to switch between octanes regularly as the engine has to re-learn to take advantage of more octane, or will experience knock when going back to a lower octane.

Towing is some of the most stressful use cases for an engine as it operates at high outputs for extended periods, with lots of heat saturation. It's where octane makes the most difference, and can be beneficial to cover for other factors.

Not saying it will definitely make a difference and will depend, but you might entertain some simple maintenance - clean the throttle body and use Seafoam through the intake track and fuel system. This can often wake up an engine and has shown to have benefits to KCLV. You might be able to get some performance back with 87.
Thanks, that’s awesome info. That does mirror what I’ve anecdotally experienced as well… KCLV was around 14-15, and it took probably 3 tanks of gas before it would creep up into the 17-18 range. It wouldn’t always stay there but it did seem to run better when it was.
 
There are definitely warnings that say not to, but I do it all the time, so let your conscience guide you.

Sooooo. Im not sure this app / reader will help with diagnosing the issue with the auto leveling headlight self-check not working any more. I think I did this right? Ill be the 1st to admit, I could be doing this wrong and I cannot find detailed instructions for the app or the scanner. FYI - the scanner in 1 place says to turn on the ignition and in another direction reads turn on OR start the car. Yet when I start the car and make the connection, I get:

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So, I tried the OBD site to make sure im doing it right, and they still dont even have pictures attached to their directions.... I tried it in Safari and Firefox - same - blank.

OBD site.jpg



Anyway. I made the connection with just the ignition on and did a scan and got no error codes.

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OR , maybe the headlight parameters that are supported are not the cause of the problem that's made the self - check not work... ??
 
Sooooo. Im not sure this app / reader will help with diagnosing the issue with the auto leveling headlight self-check not working any more. I think I did this right? Ill be the 1st to admit, I could be doing this wrong and I cannot find detailed instructions for the app or the scanner. FYI - the scanner in 1 place says to turn on the ignition and in another direction reads turn on OR start the car. Yet when I start the car and make the connection, I get:

View attachment 3396895

So, I tried the OBD site to make sure im doing it right, and they still dont even have pictures attached to their directions.... I tried it in Safari and Firefox - same - blank.

View attachment 3396903


Anyway. I made the connection with just the ignition on and did a scan and got no error codes.

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View attachment 3396906

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OR , maybe the headlight parameters that are supported are not the cause of the problem that's made the self - check not work... ??
You are kind of in uncharted waters at this point. Your best course of action would probably to get Techstream. But if you want to continue down the path with OBD Fusion, I'd make a dashboard and map some of those values to it and see if anything stands out. Especially the "Number of DTCs" one. I suspect you'll get the same information Techstream would provide, you just wouldn't have to build the dashboard (in Techstream it's called DataList) to see all the values.
 
You are kind of in uncharted waters at this point. Your best course of action would probably to get Techstream. But if you want to continue down the path with OBD Fusion, I'd make a dashboard and map some of those values to it and see if anything stands out. Especially the "Number of DTCs" one. I suspect you'll get the same information Techstream would provide, you just wouldn't have to build the dashboard (in Techstream it's called DataList) to see all the values.
What's " DTCs " ? Also, while I do see auto leveling , I dont see anywhere "self check" that they lights go through on start up.....
 
What's " DTCs " ? Also, while I do see auto leveling , I dont see anywhere "self check" that they lights go through on start up.....
DTC - "Diagnostic Trouble Code"

If you have OBD Fusion report that value, you will know if there are any stored DTCs in the headlight ECU. I don't know for sure if OBD Fusion can enumerate the DTCs for the extended networks. I would think it could. Have you tried connecting to the Network C and then running "Diagnostics" from the OBD Fusion main menu? It looks like maybe you did attempt this and got no DTCs.

There's not going to be a "self check" field. The list of fields are all the inputs that the headlight ECU takes in or the calculations/decisions on how to control the headlight system. What you would be looking for is a field that has a value that is out of spec (the FSM could tell you what the value ranges for everything should be), but some may be obvious, like an open circuit when it shouldn't be or a voltage that is too low/high. Most voltages should be near the system charging voltage (12.5-13.5v) or somewhere around 5v for some sensor inputs/outputs. If the Headlight ECU sees values that are off from the expected ranges, it probably won't trigger a "self check." Like if the headlight ECU is not getting a status/value from the rear height sensor, then the system most likely won't even attempt a self check.
 
DTC - "Diagnostic Trouble Code"

If you have OBD Fusion report that value, you will know if there are any stored DTCs in the headlight ECU. I don't know for sure if OBD Fusion can enumerate the DTCs for the extended networks. I would think it could. Have you tried connecting to the Network C and then running "Diagnostics" from the OBD Fusion main menu? It looks like maybe you did attempt this and got no DTCs.

There's not going to be a "self check" field. The list of fields are all the inputs that the headlight ECU takes in or the calculations/decisions on how to control the headlight system. What you would be looking for is a field that has a value that is out of spec (the FSM could tell you what the value ranges for everything should be), but some may be obvious, like an open circuit when it shouldn't be or a voltage that is too low/high. Most voltages should be near the system charging voltage (12.5-13.5v) or somewhere around 5v for some sensor inputs/outputs. If the Headlight ECU sees values that are off from the expected ranges, it probably won't trigger a "self check." Like if the headlight ECU is not getting a status/value from the rear height sensor, then the system most likely won't even attempt a self check.
Thanks. I thought thats what DTC meant, but wanted to make sure. I did run a scan on Network C and got no trouble codes returned.

By self check I meant, the "up and down blink" that the headlights used to make on start up. They went through an auto leveling self check, which they no longer due. I had thought that there was some way to check / scan the ECU that ive been told controls that. Part no. 89960 - 60052.

At this point seems not possible.
 
Thanks. I thought thats what DTC meant, but wanted to make sure. I did run a scan on Network C and got no trouble codes returned.

By self check I meant, the "up and down blink" that the headlights used to make on start up. They went through an auto leveling self check, which they no longer due. I had thought that there was some way to check / scan the ECU that ive been told controls that. Part no. 89960 - 60052.

At this point seems not possible.
I know what you mean by self-check. What I'm saying is that's not a "value" so there wouldn't be anything in OBD Fusion that says "self check ok" or anything like that, or certainly wouldn't necessarily be a value like that. (Added later: In looking over the PIDs from above again, it's possible that the "Status of Sensor initialization" may be exactly what you are looking for.)

Your list under "HL Autoleveling" (example: Battery Voltage Value) are called PIDs. In order to see the values reported by these PIDs, you have to add the PID to a dashboard. Once it's added then you can see the value by bringing up that dashboard.

To give you a real world example: I had a GS350 that developed a water leak in the headlight. It eventually fouled the motor that moved the projector up and down. The GS did the same self test at startup moving the headlights up and down. Once that projector motor failed, I got a stored DTC in the headlight ECU as well as the self-check at startup stopped happening. The ECU had a value that was out of range for one of its inputs (in this case the voltage response from the projector motor), so the ECU never even attempted to do the self check until I replaced the headlight, thus restoring the functionality of that projector motor.

From your picture above the Headlight ECU reports on 18 values (either inputs or reportable actions).
 
I know what you mean by self-check. What I'm saying is that's not a "value" so there wouldn't be anything in OBD Fusion that says "self check ok" or anything like that, or certainly wouldn't necessarily be a value like that. (Added later: In looking over the PIDs from above again, it's possible that the "Status of Sensor initialization" may be exactly what you are looking for.)

Your list under "HL Autoleveling" (example: Battery Voltage Value) are called PIDs. In order to see the values reported by these PIDs, you have to add the PID to a dashboard. Once it's added then you can see the value by bringing up that dashboard.

To give you a real world example: I had a GS350 that developed a water leak in the headlight. It eventually fouled the motor that moved the projector up and down. The GS did the same self test at startup moving the headlights up and down. Once that projector motor failed, I got a stored DTC in the headlight ECU as well as the self-check at startup stopped happening. The ECU had a value that was out of range for one of its inputs (in this case the voltage response from the projector motor), so the ECU never even attempted to do the self check until I replaced the headlight, thus restoring the functionality of that projector motor.

From your picture above the Headlight ECU reports on 18 values (either inputs or reportable actions).
Ok. That helps. Ill see what I can figure out. Thanks a bunch!
 
I know what you mean by self-check. What I'm saying is that's not a "value" so there wouldn't be anything in OBD Fusion that says "self check ok" or anything like that, or certainly wouldn't necessarily be a value like that. (Added later: In looking over the PIDs from above again, it's possible that the "Status of Sensor initialization" may be exactly what you are looking for.)

Your list under "HL Autoleveling" (example: Battery Voltage Value) are called PIDs. In order to see the values reported by these PIDs, you have to add the PID to a dashboard. Once it's added then you can see the value by bringing up that dashboard.

To give you a real world example: I had a GS350 that developed a water leak in the headlight. It eventually fouled the motor that moved the projector up and down. The GS did the same self test at startup moving the headlights up and down. Once that projector motor failed, I got a stored DTC in the headlight ECU as well as the self-check at startup stopped happening. The ECU had a value that was out of range for one of its inputs (in this case the voltage response from the projector motor), so the ECU never even attempted to do the self check until I replaced the headlight, thus restoring the functionality of that projector motor.

From your picture above the Headlight ECU reports on 18 values (either inputs or reportable actions).
Ok. Here are some I did. But, I have no idea what the defaults are suppose to be. The Rear Height value looks odd - but - dont know what its suppose to be. Also, I posted this one before, not related to the lights though, maybe the O2 sensor is off??

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I'd agree it's related where the engine is backing off timing (and power) as a result of learning. Add KCLV (Knock Correction Learn Value) to your dash. This should be the clearest indication of timing compensation. It's a learned value where the ECU will advance until it sees some detonation. Based on your symptoms, I would expect to see a relatively lower KCLV values on 87. And relatively higher values with 91. The number isn't static exactly and does change with elevated heat and load, but it is a longer term trim value.

Not that the LC requires 91, but you're using the vehicle in a very stressful manner of high load and high rpm. With tuning experience from my track days, the engine is heat soaking with elevated oil, coolant, and overall temps that it's pulling timing. Many cars with factory 87 octane tunes can benefit from higher octane fuels, as they are less volatile and resistant to pre-ignition under longer durations of extreme throttle like accelerating down the back straight or towing. Stuff normal cars don't see.

This could also be related to fuel system vapor/boiling issues in that the fuel is so heat soaked that its elevated heat and vapor pressure is contributing to the pulled timing.

I have KCLV at the bottom left. I generally see values of 18-19. This is during a high stress climb towing.

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Was watching KCLV on the way home from work on the highway today and noticed anything between 9.4 and like 12.0 at the highest. I havent seen anyone mention values on that low end yet. 2018 stock with 60k miles and fairly babied to this point. If I'm interpreting everything I've read in here and elsewhere on the interwebs that doesn't seem desirable. Is that a safe assumption? And if so is changing to 91 octane the first course of action? Does outside / intake air temperature have an effect on this? Was about 105 outside and IAT like 125-130.
 
Was watching KCLV on the way home from work on the highway today and noticed anything between 9.4 and like 12.0 at the highest. I havent seen anyone mention values on that low end yet. 2018 stock with 60k miles and fairly babied to this point. If I'm interpreting everything I've read in here and elsewhere on the interwebs that doesn't seem desirable. Is that a safe assumption? And if so is changing to 91 octane the first course of action? Does outside / intake air temperature have an effect on this? Was about 105 outside and IAT like 125-130.

KCLV is somewhat a magic number and the ranges I indicated may only be relevant for certain models. It's highly likely that post-2016 has a different calibration and possibly even different tuning strategies. It would be hard to say what you're seeing in outside normal without a larger sample size.

The IATs you're seeing aren't out of normal for summer and the ECU has maps to compensate for that factor so it wouldn't rely on KCLV.

Perhaps someone else with a 2018 LC can weigh in?
 
Export your dashboard now! I got a new phone and had to go through the setup routine again. I was on the road before realizing that I had not loaded the Toyota Lexus Scion pack and dashboard. Today I powered up my Note 9 and exported the dashboard to my dropbox and imported it on the Galaxy 23 Ultra. I saved a lot of time but not until after sweating a trip to Waco and back with a dual axle cargo hauler with 2 of my kids apartment stuff for the new semester a Baylor. Probably not heavy enough to really worry but the ambient is 108 F. So, before you destroy, lose or update your smartphone, export the dashboard. I spent quite a bit of time modifying @linuxgod 's dashboard for my 2020 and am glad I don't have to do that all over again.
 
So my first link in currently post 48 has the OBD module dashboard (in my files I now call that "trip") and that one has my new edited "Trip" dashboard and probably a messed up version of Teck's dashboard, the one you pictured.



I now have them separated on my google drive so ill provide two cleaner links here.

Trip Dashboard

AHC Dashboard

If you downloaded both my previous two files, you should have ended up with 3 dashboards total. A borked up Teck dashboard, and then my Trip and AHC dashboards.

Also, I've done all my editing on the iPhone (11 Pro Max). Not my ideal medium but I'm not going to put the effort/cost into making a better way to do it, since it's probably pretty much at the limits of what you can do within the OBD Fusion framework.

Thanks for sharing. Pretty slick dashboards. I can get the Trip one to work, but the AHC one just constantly reads 0. Any ideas?

I realize the data for the AHC dashboard is under a different network (E) than the network for the Trip dashboard (A). It is saying this module has not been scanned - is it an either or, as in I can only select one network at a time and therefore only one dashboard can read out at a time? Or is there a way to scan all the networks upon start up?
 
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Thanks for sharing. Pretty slick dashboards. I can get the Trip one to work, but the AHC one just constantly reads 0. Any ideas?

I realize the data for the AHC dashboard is under a different network (E) than the network for the Trip dashboard (A). It is saying this module has not been scanned - is it an either or, as in I can only select one network at a time and therefore only one dashboard can read out at a time? Or is there a way to scan all the networks upon start up?
Yes, you can only use one dashboard at a time and have to switch networks to move between them.
 
Thanks. And you have to scan the other network before switching between the dashboards, which seems to take a few minutes for me, each time?
You should only have to do a "scan" once. The E network does take quite a bit longer to load though compared to the Generic OBD/Network A. But i wouldn't say that it takes minutes. I'd say more like 10-15s.
 
You should only have to do a "scan" once. The E network does take quite a bit longer to load though compared to the Generic OBD/Network A. But i wouldn't say that it takes minutes. I'd say more like 10-15s.
Thanks. It does it need to scan during each start up or just scan once and then already “linked” upon subsequent trips?
 
Thanks. It does it need to scan during each start up or just scan once and then already “linked” upon subsequent trips?
It's been a while since i messed with it, but as long as you let the scan from the settings menu complete, it should only need to do that one time. Then from there you can select which network you want to load in settings or you can use the "prompt" option in that menu and then every time OBD Fusion boots up it will ask you which netwokr you want to connect to.
 
KCLV is somewhat a magic number and the ranges I indicated may only be relevant for certain models. It's highly likely that post-2016 has a different calibration and possibly even different tuning strategies. It would be hard to say what you're seeing in outside normal without a larger sample size.

The IATs you're seeing aren't out of normal for summer and the ECU has maps to compensate for that factor so it wouldn't rely on KCLV.

Perhaps someone else with a 2018 LC can weigh in?
I've switched to 91 octane for the last few tank's and am consistently seeing higher KCLVs now on my very repeatable drives to and from work. I had been consistently between 10 and 12 and now on 91 octane am consistently between 13 and 15 for what it's worth. Also see about .5 to 1 mpg better mileage. Not 10% better to match the 10% higher cost but I think I'll stick with it.
 

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