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Just a quick update on the G37 mini-dash / guages I have been working on.
This version shows 35 unique data items (see full list below video link), on 16 different pages, that are meaningful for the 370 enthusiast.
To change the displayed page, just push the cruise on/off button twice within 1.5 seconds. Super easy!
Also, when your headlights turn on and the dash dims, so does the gauge back light. No illumination wiring needed!
Once the snow clears, the next video will show the gauge operation while going for a drive in the country.
Full list of available data items: Data items from the "Bluetooth Sensor Server" and additional sensors:
• Engine oil pressure
• Fuel pressure
• Manual transmission oil temperature
• Differential oil temperature
• up to 4 additional temperature, pressure or even ethanol sensors.
From the car's network (CAN bus)
• ECT: Engine coolant temperature
• EOT: Engine oil temperature
• EOP: Engine oil pressure
• AFR B1: Air/fuel ratio bank 1
• AFR B2: Air/fuel ratio bank 2
• Individual wheel speed
• MAF 1: Mass air flow, bank 1
• MAF 2: Mass air flow, bank 2
• IAT: Intake air temperature
• MAP: Intake manifold pressure (aka boost sensor)
• TB 1: Throttle body absolute position bank 1
• TB 2: Throttle body absolute position bank 2
• APP: Accelerator pedal position
• IGN: Cylinder #1 ignition timing
• TORQ: Engine torque
• HP: Calculated HP (from engine torque & engine RPM)
• AWD: Front wheel torque. 0% = RWD only, 100% = fully AWD and 50/50 torque split
• SIDE g: Lateral acceleration
• STRG: Steering wheel angle
• TOT: Automatic transmission fluid temp
• IN RPM: Automatic transmission input shaft RPM
• OUT RPM: Automatic transmission output shaft RPM
• GEAR: Automatic transmission current gear (1-7)
• Automatic transmission torque converter status: Locked or Sliding
• BRAKE PSI: Brake line pressure
• BARO: Outside air pressure
• OUT TEMP: Outside air temp
• CRUISE: Cruise control set speed
• RAD FAN: Rad fan duty cycle. 0% = off, 100% = full speed
• VOLTS: System voltage
• CFM: Calculated, real time engine air flow in cubic feet per minute. Uses intake air temperature and outside air pressure to calculate intake manifold air density and uses the total mass air flow to calculate actual engine air flow.
Awesome work thus far, Frank. Thank you for spearheading this project!
Originally Posted by MotorvateDIY
To change the displayed page, just push the cruise on/off button twice within 1.5 seconds. Super easy!
Out of curiosity, will the end user be able to remap to a different button or is this permanently hard-coded to use the cruise button? I ask this because I use a Q60 (CV37) steering wheel and have two unused buttons which would be ideal for this use.
Last edited by ILM-NC G37S; Mar 13, 2022 at 10:11 AM.
Awesome work thus far, Frank. Thank you for spearheading this project!
Out of curiosity, will the end user be able to remap to a different button or is this permanently hard-coded to use the cruise button? I ask this because I use a Q60 (CV37) steering wheel and have two unused buttons which would be ideal for this use.
Thanks for your kind words!
I can use any button that broadcasts on the car's main CAN bus network... For the V36/Z34 that is just the crusie on/off button.
Every other button is typically wired directly to its module, so there is no need for CAN bus communication.
(cruise set/resume/speed up/speed down/cancel are wired to the ECU. All audio buttons are wired to the AV/ITM module)
Other than the AV CAN, where every AV/NAV & AC button press is broadcast, but I really don't want use that, as it requires an additional CAN bus transceiver, controller and more code.
In the next few weeks, I will be meeting up with a few Q50 owners to record the CAN bus and test gauge functionality.
It would be very helpful if you could show/tell me about the unused buttons on the steering wheel as I would need to press them while recording the car's CAN bus to find it in the massive sea of data that is constantly being broadcast
The good news is that the newer Nissan/Infiniti vehicles seem to use the CAN bus much more for communication, and much less for directly wired communications/button presses.
The bad news is that around 2018/2019 Nissan/Infiniti added a CAN bus gateway, which blocks the broadcasts from the OBD port.
However, it should be fairly easy to work around that.
This is what I have. These are the two switches I am curious about:
Now keep in mind that on the Q's these two switches are what scrolls between the different items on the gauge cluster LCD screen. On the Q's, this little screen has more "informative" bits than the G's. (Believe me, if I could get that cluster to work I would have already (damn fuel gauge)...
Retrofitted to the G, these two buttons do nothing (understandable). The Q60 FSM has these circuits (STEER A, STEER B) wired directly to the cluster which, likely, acts as a gateway of some sort to the CANBUS whereas on the G the ITM/AV unit is the "middle man."
¯\_(ツ)_/¯
Something to consider if your module will also be targeted to other models. Just thinking out loud...
Last edited by ILM-NC G37S; Mar 13, 2022 at 12:18 PM.
This is correct. 2018 Q60 Red Sport wheel on a 2008 G37 (had to have the heated wheel)...
The steering wheel switches are fully connected using the same 3-wire system. However, being that each button has a different resistor value assigned, the G37 does not have a specific "command" to execute when the control voltage from those resistors are read/ ie. buttons are pressed.
The microcontroller I use does have free ADC pins and it could easily determine when those buttons are pushed.
All that would be needed is to tap into those wires. I will make of note of this and come back to it down the road, I really want to keep focused on a standard package and code to starts.
Thanks for the suggestion!
The microcontroller I use does have free ADC pins and it could easily determine when those buttons are pushed.
All that would be needed is to tap into those wires. I will make of note of this and come back to it down the road, I really want to keep focused on a standard package and code to starts.
Thanks for the suggestion!
Hi Motorvate,
This is so cool what you are doing. Can you estimate when we can buy this scanner?
Hi Motorvate,
This is so cool what you are doing. Can you estimate when we can buy this scanner?
Thanks!
My best guess is late spring or early summer, all depending on how well the testing goes and how long it takes to get the parts (like LCD displays)
Due to covid, it has been difficult to test it on different versions of the G37, but that is now getting better.
Last week I found out that if the G37 has ICC (intelligent cruise control) the data on the CAN bus is different and wasn't able to change the page.
I have updated the code and need to re-test it again.
I don't have much experience with making/selling a commercial product, so there will be a lot of testing to make sure it is solid and then a slow roll out.
March 31 Update:
Have you ever wanted a manual gear position indicator/display on your G37 USING the factory gauges?
Even without a gear position sensor this is possible.
Don't believe me?
Watch the video
We have found the CAN bus message to display the gear numbers 1 to 8 ON THE FACTORY LCD in the gauge cluster. Why would the cluster show 8th gear? Well in Japan, there was a version of the G37 sold with a "high torque" CVT type transmission and it "simulated" 8 gears... so the gauge cluster must also show 8 gears.
Now, since we can control what gear number is displayed via a CAN bus message, how do we figure out what gear we are in?
On the G37 there are no position sensors, just a switch for reverse and a switch to indicate neutral...
Well... If you divide the engine RPM, by the vehicle speed, you end up with a number that is fairly constant when in that gear.
For example, 1st gear results in 115, second gear is 68.
Now that we know the gear, we fire off the correct CAN bus message to tell the middle LCD display in the factory cluster to display that number.
This works perfectly when the clutch is fully released.
However, when the clutch is slipping (like during a start) or if in neutral and rolling to a stop, the indicated gear may not be accurate.
We are going to continue testing and see what strategies we can use to reduce or prevent this.
I will have the last update video out in the next few days.
Last edited by MotorvateDIY; Mar 31, 2022 at 01:09 PM.
I think this would be even more useful for the AT folk when in auto mode (not manual). Most MT drivers know what gear they're in at any given time. The G gear box is none sequential so it's more a physical position of the lever that indicates what gear one is in. For example, modern motorcycles use sequential gears - 1 down, N, 5 up. There a gear position indicator is helpful as there's no tactile way of know what gear you're in.
Clever idea.
I think this would be even more useful for the AT folk when in auto mode (not manual). Most MT drivers know what gear they're in at any given time. The G gear box is none sequential so it's more a physical position of the lever that indicates what gear one is in. For example, modern motorcycles use sequential gears - 1 down, N, 5 up. There a gear position indicator is helpful as there's no tactile way of know what gear you're in.
Understood... As you know, when you drive a manual transmission you know the gear you are in either by feel, rpm or a glance at the shifter.
However, after saying that, I am enjoying seeing the gear in the cluster more than I thought.
For the folks with the automatic transmissions, I do have a display that shows:
• Transmission fluid temp (TOT - transmission oil temp)
• Current gear 1-7
• Input shaft RPM / output shaft RPM
• Torque converter status: (locked or sliding / TC L = Torque Converter Locked)
I can't display the actual gear in the cluster, since the TCM is already doing that.
That's why this works on the manual G... no competing modules
I think some of this information might be helpful to understand why some have such a bad lag issue...
Could it be as simple as the transmission not down shifting or the torque converter no unlocking?
Additional item:
I have tested this on a VHR Q50 and everything worked. In a few weeks, I have a few volunteers and will test on the VR Q50s
They *REALLY* want a boost gauge and AWD torque!
