GR Yaris CAN Bus Reverse Engineering
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bahamutkotd
New member
So seems like in the US GR Corolla harness this connector is actually inverse connector called I174 and has been what i've been looking for more information on for like since i found out about it early this year, I've been planning on using a esp32 based adafruit board with a can tranciever and a sd card to make a can logger, but was kinda lost when there wasn't any decoding information. I'll be checking out your repo shortly! Is this a spot to get engine info or would it need to be spliced into the engine can or OBD2 to get the same kind of stuff as ecutek uses?
Edit: Do you have the toyota part number for the H56 connector? or has anyone been able to find the mate for the can gateway it is a 34 pin connector.
Edit2: part numbers for the 2 connectors if I’m correct is 90980-12936 and 90980-12937
Edit: Do you have the toyota part number for the H56 connector? or has anyone been able to find the mate for the can gateway it is a 34 pin connector.
Edit2: part numbers for the 2 connectors if I’m correct is 90980-12936 and 90980-12937
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tonic
Totally Hooked
- Aug 31, 2023
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- #24
All testing I’ve done is based on the GR Yaris Gen1, though I have some information that these CAN IDs also seem to work on the Gen2. I have no idea about the GR Corolla, but I suspect most of them should work. Your part numbers are correct.
As for the mating connector for the CAN Gateway, I tried buying a Gateway module from a hybrid Yaris in order to salvage the male connector. The connector is an SMT type with very thin tabs, which would be a nightmare to solder, and I don’t think it would last. But then I found an AliExpress listing for something that looks like it should work. I ordered two, but they still haven’t arrived, so I can’t confirm if they fit:
www.aliexpress.com
As for the mating connector for the CAN Gateway, I tried buying a Gateway module from a hybrid Yaris in order to salvage the male connector. The connector is an SMT type with very thin tabs, which would be a nightmare to solder, and I don’t think it would last. But then I found an AliExpress listing for something that looks like it should work. I ordered two, but they still haven’t arrived, so I can’t confirm if they fit:
34 Pin Auto Instrument panel host connector DCM module ECU plug 90980-12E32 90980-12E35 6098-8852 6098-8854 For Toyota Lexus - AliExpress 13
Smarter Shopping, Better Living! Aliexpress.com
www.aliexpress.com
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bahamutkotd
New member
It was driving me crazy, trying to find the socket, and like you I was only able to find the Aliexpress chinesium parts. I also found that TE makes a 40 pin that seems compatiable but the male pins indeed only come as smt. I think stratified is using those aliexpress parts as basis for their flexfuel kit.All testing I’ve done is based on the GR Yaris Gen1, though I have some information that these CAN IDs also seem to work on the Gen2. I have no idea about the GR Corolla, but I suspect most of them should work. Your part numbers are correct.
As for the mating connector for the CAN Gateway, I tried buying a Gateway module from a hybrid Yaris in order to salvage the male connector. The connector is an SMT type with very thin tabs, which would be a nightmare to solder, and I don’t think it would last. But then I found an AliExpress listing for something that looks like it should work. I ordered two, but they still haven’t arrived, so I can’t confirm if they fit:
34 Pin Auto Instrument panel host connector DCM module ECU plug 90980-12E32 90980-12E35 6098-8852 6098-8854 For Toyota Lexus - AliExpress 13
Smarter Shopping, Better Living! Aliexpress.com
bahamutkotd
New member
Where do you find documentation like this?Thanks, man! I'll add them to the list and tidy up my naming.
No, I believe it's the real-time fuel supply for the engine in ml. It could potentially be used for momentary or average fuel consumption on your dash.
According to diagram, H62 is connected to the Bus Buffer ECU (Bus 7). I'm not entirely sure what that meansbut I am definitely seeing signals from various buses, not certain if it's from all of them.
View attachment 33129
View attachment 33130
liusername
New member
- Nov 13, 2025
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@tonic
@xpertleader
I need some help with the collective brain trust. I too have been working on adapting this to work with my AIM Solo2 DL and I can't seem to get it to work.
The harness:
It's not super elegant but it should work just fine. I've decided not to cut the AIM OBD2 cable just because I might use it on another car, so from the SOLO, it connects to an existing splitter that I felt much happier about cutting up.
All it gets from the OBDII port on the car is power and ground via one of the deutsch connectors.
One could argue that a splitter is entirely unnecessary, but I have an ECUTEK dongle that I like to keep connected so that I can switch power maps on the fly.
On the other deutsch connector, I have it connected to the H62 port via a CAT6 cable. I own a LHD model so @tonic 's post was very helpful in locating it.
Below is my RaceStudio3 custom CAN template that was once again possible thanks to this thread.
Bit rate is set at 500 Kbit/sec, 120 ohm resistor is disabled, and the device is silent.
As for where testing currently stands, power and ground obviously work because the SOLO starts charging when I plug it in.
Between CAN HI and LOW on the SOLO harness, I'm getting 120.4 ohms.
Measuring between CAN HI <--> GND (cigarette lighter), I'm getting anywhere between 0.5V and 3.5V depending on when I measure. Similar situation for CAN LOW <--> GND.
It does feel like the H62 gateway goes to sleep quite easily. I can't quite figure out when or why, but it's quite often that I'll measure the voltage of each CAN wire and they'll be at around 0V which is quite frustrating.
As of right now, I'm not picking up anything on the SOLO or in the software on my laptop. I really, really want to figure this out and maybe write a proper tutorial because I feel like it's this close to working and we can hopefully share and help others down the road.
Any and all input welcome! Thanks in advance.
My car for attention (I usually only post on the other forum)
@xpertleader
I need some help with the collective brain trust. I too have been working on adapting this to work with my AIM Solo2 DL and I can't seem to get it to work.
The harness:
It's not super elegant but it should work just fine. I've decided not to cut the AIM OBD2 cable just because I might use it on another car, so from the SOLO, it connects to an existing splitter that I felt much happier about cutting up.
All it gets from the OBDII port on the car is power and ground via one of the deutsch connectors.
One could argue that a splitter is entirely unnecessary, but I have an ECUTEK dongle that I like to keep connected so that I can switch power maps on the fly.
On the other deutsch connector, I have it connected to the H62 port via a CAT6 cable. I own a LHD model so @tonic 's post was very helpful in locating it.
Below is my RaceStudio3 custom CAN template that was once again possible thanks to this thread.
Bit rate is set at 500 Kbit/sec, 120 ohm resistor is disabled, and the device is silent.
As for where testing currently stands, power and ground obviously work because the SOLO starts charging when I plug it in.
Between CAN HI and LOW on the SOLO harness, I'm getting 120.4 ohms.
Measuring between CAN HI <--> GND (cigarette lighter), I'm getting anywhere between 0.5V and 3.5V depending on when I measure. Similar situation for CAN LOW <--> GND.
It does feel like the H62 gateway goes to sleep quite easily. I can't quite figure out when or why, but it's quite often that I'll measure the voltage of each CAN wire and they'll be at around 0V which is quite frustrating.
As of right now, I'm not picking up anything on the SOLO or in the software on my laptop. I really, really want to figure this out and maybe write a proper tutorial because I feel like it's this close to working and we can hopefully share and help others down the road.
Any and all input welcome! Thanks in advance.
My car for attention (I usually only post on the other forum)
tonic
Totally Hooked
- Aug 31, 2023
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- #30
It looks like you’re doing everything right. From what I’ve seen, the H62 never really goes into sleep mode.
Few things to try:
If none of that works, I’d suggest getting an oscilloscope and checking if you’re getting a proper CAN signal on the OBDII port you’re connecting your AIM Solo to.
Few things to try:
- Make sure you haven’t mixed up CAN High and CAN Low between the H62 and your OBDII socket.
- Try enabling the CAN bus termination resistor, the bus needs termination on both ends. I guess you already tried this
- You don’t need 29 bit filtering as there are no extended CAN IDs configured. Just leave the 1–11 filters enabled.
If none of that works, I’d suggest getting an oscilloscope and checking if you’re getting a proper CAN signal on the OBDII port you’re connecting your AIM Solo to.
liusername
New member
- Nov 13, 2025
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Alright, time for a quick update.
It turns out that in my rush I did actually reverse HI and LOW. Luckily that's a one minute fix so it wasn't an issue.
I left bytes 0~10 checked and everything else unchecked, uploaded the new settings, and voila, we have some readings!
...And that's kind of where the good news ends.
The new problems are twofold:
1) Data updates super slowly, like maybe 0.5Hz ish if I'm lucky
2) The gateway only stays active for about 30 seconds after startup, or immediately after engine shutdown
These pics were taken a couple of seconds apart- the readings were cutting in and out.
I'm not sure if it's a model year or geographic difference between our cars, but it feels like the bus on H62 behaves a little differently on mine.
As I mentioned, as soon as I turn the car off, the display values suddenly come alive at about 1Hz before turning off a few seconds later. It sucks that the forum doesn't allow video attachments because I have some examples.
Not really sure where to go from here. I think I can try looking for a different access location for CAN data. I don't really want to go back to being stuck on OBD2 only because that takes away like 90% of the functionality the Solo offers.
Thanks for all the help! I'll keep looking and post any updates if I get anywhere.
It turns out that in my rush I did actually reverse HI and LOW. Luckily that's a one minute fix so it wasn't an issue.
I left bytes 0~10 checked and everything else unchecked, uploaded the new settings, and voila, we have some readings!
...And that's kind of where the good news ends.
The new problems are twofold:
1) Data updates super slowly, like maybe 0.5Hz ish if I'm lucky
2) The gateway only stays active for about 30 seconds after startup, or immediately after engine shutdown
These pics were taken a couple of seconds apart- the readings were cutting in and out.
I'm not sure if it's a model year or geographic difference between our cars, but it feels like the bus on H62 behaves a little differently on mine.
As I mentioned, as soon as I turn the car off, the display values suddenly come alive at about 1Hz before turning off a few seconds later. It sucks that the forum doesn't allow video attachments because I have some examples.
Not really sure where to go from here. I think I can try looking for a different access location for CAN data. I don't really want to go back to being stuck on OBD2 only because that takes away like 90% of the functionality the Solo offers.
Thanks for all the help! I'll keep looking and post any updates if I get anywhere.
geraldjust
New member
- Dec 6, 2025
- 1
- 5
hey guys! im making a logging cable, but need some people to verify the fitment. the cable will connect to the options connector. and its has both the male and female side so it will work for both GRC and GRY. and the cable uses the factory obd2 port to get the power and ground pins for the AIM to also charge while logging.
besides that i set up my AIM profile, i reversed engineered myself most of the values the ecu outputs. so all of the temp stuff, so have the oil temp. oil pressure, i also verified the brake pressure by logging via techstream to verify my units. so my values are tested on a grc. so not sure if they will match a GRY.
anyways if anyone wants to test my cable let me know. GRY that are RHD would be nice as well
besides that i set up my AIM profile, i reversed engineered myself most of the values the ecu outputs. so all of the temp stuff, so have the oil temp. oil pressure, i also verified the brake pressure by logging via techstream to verify my units. so my values are tested on a grc. so not sure if they will match a GRY.
anyways if anyone wants to test my cable let me know. GRY that are RHD would be nice as well
bahamutkotd
New member
From preliminary testing it seemed that it would fit across the dash of the left hand drive cars
Bit of a different topic, but hoping someone could shed a little light on whether this is feasible.
Is there any way to make changes on the CAN BUS so that the hazard lights stop flashing when the ABS kicks in? I believe this is called ESS and I want to disable it.
Is there any way to make changes on the CAN BUS so that the hazard lights stop flashing when the ABS kicks in? I believe this is called ESS and I want to disable it.
bahamutkotd
New member
If the abs system is sending a can message triggering the controller that controls the tail lights then perhaps you could send the message with the light disabled. Right after but the bulbs would flash for a very short time. But this has some downsides obviously increased wear on that part, and it might be possible to prevent this the message will be ignored if sent at a rate faster than expected for security reasons.
That of course assumes that the abs is sending a CAN message to control that. And not just triggering the relay it’s self.
Edit: The hazards and turn signals are controlled directly by the dash screen. So, it might be customizable with the proper tools.
That of course assumes that the abs is sending a CAN message to control that. And not just triggering the relay it’s self.
Edit: The hazards and turn signals are controlled directly by the dash screen. So, it might be customizable with the proper tools.
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tonic
Totally Hooked
- Aug 31, 2023
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- #37
Yes, it's possible but for that you have to intercept CAN frames going to the instrument panel.
There is a solution for that: https://www.btech-shop.com/products/adaptive-assistance-control-gryaris
bahamutkotd
New member
God another product that has the 34 pin socket that interfaces with the network gateway… I swear that has to be a part produced by some company… drives me crazy I can’t find who makes the stupid thing…
tonic
Totally Hooked
- Aug 31, 2023
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- #39
From what I see, they interface with the instrument cluster, not the gateway.
As for the gateway connector, I believe Sumitomo makes it for Toyota, and the male side is only available as an SMD type used in the gateway itself. I tried buying a used gateway from a regular Yaris to cannibalise the connector, but the pins going into the PCB are far too flimsy for a standalone setup. Other than that, the only option I’ve found is the Chinese one, and it’s crap. I believe you’ve tried that one as well.
bahamutkotd
New member
I haven’t tried it but I keep seeing products use it. The stratified flex fuel kit, autoharnesshouse has a dcm delete there is a Swiss company that has a man in the middle chime ignore.
