1997 Land Cruiser OBD FUSION App Question

[Zjohnsonua]

I haven't found a list of ODBII signals; I doubt one exists publicly. If it does, someone has backtraced it.

If I understand you correctly, the transmission temperature signal, as near as I can make out, is only connected to the high limit switch on the ECU, which is also connected to the light (not the MIL, for some reason) on the combo meter.

Toyota, in its infinite wisdom decided to shut off the engine if the engine oil level is low, but not if the transmission overheated. Maybe they thought the likelihood of occurrence was too low to warrant it. Anyway, I can't find any documentation to suggest the signal goes anywhere else.

AFAIK, there is no OBDII transmission temperature signal at all. The Toyota test equipment may have access to it, but the OTC OBDII tools do not. It would be nice if there was a factory Toyota tech on here that had access (either currently or in the past) to the dealer tools who could say for sure. I haven't tried using Techstream to find the signal; I'll put that on the list.

OBDII supports trans temp and many others that aren't regularly used (described in the very dry and nerdy SAE J1979 standards). I have it active as a built in PID via Torque Pro, which is using a clustered set of PIDs based on which model you select. I forget where I found it in the app, but it wasn't intuitive.

 

[Malleus]

Share, share, share!

 

[Malleus]

Well, that gets half my problems solved for me. Looks like it's up to me to carry water for the '93-'94 crowd.

@jpoole, FWIW, I think the difference between the OBD I and OBD II signals is the pulse output to the annunciator (combo meter). The raw sensor data stream should be the same, at least for all the sensors that are the same for 1993-1997.

 

[DirtyPepper]

Apologies for highjacking your thread, but the perfect solution would be to create a board to send the OBDII and other desirable signals to, and then display that information.

Ideally you'd want to tap into the leads at the ECU terminals under the glovebox (which would be straightforward) and then you could mount the display wherever you wanted (like in that useless hole under the mid vents). That way, you wouldn't be constantly knocking your knee on the WiFi module and you could grab more data than the current OBDII phone apps provide for. A simple Arduino board could also send bluetooth signals so you could set alarms on your phone or mirror the whole display, if you wanted to do that. (I'd personally rather have the dash display, but I'm a Luddite)

For example:
View attachment 3281068

Someone in the great white north (@Nasr Qaisar) has something similar for 40s going on now (posted this or last week). @jpoole should check that thread out; might be fun for a weekend's work on a rainy couple of days. (Image above not the 40 solution; completely different application)

My friend, you can ALWAYS hijack a thread of mine. Your info is INVALUABLE AND APPRECIATED!

Good lord...that's awesome!

 

[mudgudgeon]

Obviously, OBD I/II protocol is published (or you would be able to buy the cables).

Typo in this sentence^^ ?

Well, that gets half my problems solved for me. Looks like it's up to me to carry water for the '93-'94 crowd.

@jpoole, FWIW, I think the difference between the OBD I and OBD II signals is the pulse output to the annunciator (combo meter). The raw sensor data stream should be the same, at least for all the sensors that are the same for 1993-1997.

Have you looked into the toyobd1 reader?

I picked one up and have been using the app.

Something I read, either within the app, or maybe the description of the app on the Google Play store said obd1 reads data every 1.5 seconds. Obd2 reads at a much closer interval.

I was looking through configuration options in the app, there's no preloaded configuration for a 1fz-fe with manual trans. You can create a custom configuration, but I haven't dug into that enough to get a good grasp on what the options are.

ZF scantools (toyobd1) website is blank. And the Facebook user group is private, and so far request for access have been addressed.

 

[mudgudgeon]

@Malleus let me know if photos of the inside of toyobd1 scan tool would help.

I'd also happily send it to you to reverse engineer, but currently have a need for it to trouble shoot my truck

 

[Malleus]

Typo in this sentence^^ ?




Have you looked into the toyobd1 reader?

I picked one up and have been using the app.

Something I read, either within the app, or maybe the description of the app on the Google Play store said obd1 reads data every 1.5 seconds. Obd2 reads at a much closer interval.

I was looking through configuration options in the app, there's no preloaded configuration for a 1fz-fe with manual trans. You can create a custom configuration, but I haven't dug into that enough to get a good grasp on what the options are.

ZF scantools (toyobd1) website is blank. And the Facebook user group is private, and so far request for access have been addressed.

EDIT:
I do think I saw this years ago, and again just recently; someone was selling his reader (it went in minutes). The comment was made that the guy who made these has stopped and has fallen off the planet.

Yes, a good quality photo would help reverse engineer it. It can't be much. Hopefully someone reading this has some connection and we can get his blessing

---

Well, that's timely!
I haven't seen this; he needs to advertise here. I couldn't find anything about the hardware, just his post on ToyotaNation describing the software. Do you have a hardware purchase link? If the ZFScantools website is his sales point, he's hiding his stuff well...

What would you think the typo was? maybe, but I didn't see it, if it's there.

 

[mudgudgeon]

Well, that's timely!
I haven't seen this; he needs to advertise here. I couldn't find anything about the hardware, just his post on ToyotaNation describing the software. Do you have a hardware purchase link? If the ZFScantools website is his sales point, he's hiding his stuff well...

What would you think the typo was? maybe, but I didn't see it, if it's there.

Toyobd1 scan tool has been around since 2016, but haven't been available for sale consistently (made in batches) and haven't been available for sometime I believe.
I picked mine up from a mud member.

It may be worthwhile downloading the app and seeing what you can gleen from that

 

[mudgudgeon]

Obviously, OBD I/II protocol is published (or you would be able to buy the cables).

Wasn't sure if you were saying protocol is/isn't published, or you would/wouldn't be able to buy cables.

The adapter cables from obd1 to obd2 plug still don't let you read obd1 data do they?

 

[mudgudgeon]

EDIT:
I do think I saw this years ago, and again just recently; someone was selling his reader (it went in minutes). The comment was made that the guy who made these has stopped and has fallen off the planet.

That was probably me who grabbed it!

There's a long thread in here and people were posting PSA everytime a batch became available, but they vanished fast everytime

 

[Malleus]

Wasn't sure if you were saying protocol is/isn't published, or you would/wouldn't be able to buy cables.

The adapter cables from obd1 to obd2 plug still don't let you read obd1 data do they?

I meant to say only the standard protocol (the description of what the standard pin arrangement does what and the data transfer rates) is available. Both the description and the cables to connect to both OBD I and OBD II data ports are readily available.

An OBD I (the DLC 1 connection on the firewall) to OBD II (the DLC 3 connector near the fuse panel) cable will allow you to read the signals, you just have to have software which will interpret the signals you read. That's what the magic box does. There's (likely) an EProm (erasable, programmable memory chip) on the board that does all that. You just need code and a chip writer to set the instructions on the chip.

The chip (individually numbered) pins have time and signal (actually, voltage) setpoints in the code and when those thresholds are reached, the signal goes out from a particular pin, to another device (resistor, capacitor, diode, etc) on the board, and then, usually, to a LDC screen or a bluetooth transmitter.

In the case of the ECU in the truck (the analog to the reader board we're discussing here), once a signal comes in (for example, engine speed input), a signal goes to another device: for example, the AFM/MAF to control the amount of air at the intake and thus the air/fuel ratio.

 

[ppc]

In the case of the ECU in the truck (the analog to the reader board we're discussing here), once a signal comes in (for example, engine speed input), a signal goes to another device: for example, the AFM/MAF to control the amount of air at the intake and thus the air/fuel ratio.

I think your understanding of how engine control systems work is bass ackwards. As an example the AFM or MAF measures the amount of air flowing into the engine. It doesn't control the amount of air.

 

[mudgudgeon]

I think your understanding of how engine control systems work is bass ackwards. As an example the AFM or MAF measures the amount of air flowing into the engine. It doesn't control the amount of air.

Sure, maybe.
I took it as a basic description/ comparison between an in vehicle system vs a read out of the data from that system. Not an in depth explanation of the working intricacies of an EFI system.

 

[Malleus]

I think your understanding of how engine control systems work is bass ackwards. As an example the AFM or MAF measures the amount of air flowing into the engine. It doesn't control the amount of air.

I never said it did. Probably a good idea to read before flaming.

Appreciate your helpful insight, though.

 

[Outsane]

OBDII supports trans temp and many others that aren't regularly used (described in the very dry and nerdy SAE J1979 standards). I have it active as a built in PID via Torque Pro, which is using a clustered set of PIDs based on which model you select. I forget where I found it in the app, but it wasn't intuitive.

If you can find the pid info to display trans temp on torque pro or scangauge 3 that would be awesome