[zolck510]

I have an OBDLink MX+ which I'm trying to get it to read current transmission gear position with.
It has a built-in "Transmission Actual Gear Status" PID which does not seem to actually display any info.
I'd like to get something beyond the "P, R, N, D" status as in actual 1st, 2nd, 3rd gear etc.
Has anyone successfully done this before? It does not necessarily have to be with the OBDLink app since I do have a bluetooth reader and can use any other app. Thanks.

 

[datsa noydb]

I have heard it's possible with a ScanGauge II.

Not sure it it's a standard feature or if you need to load some 'extra' software.

.

 

[zolck510]

I actually figured it out while playing around with a huge list of PIDs.

I'm using the OBDLink MX+ so all the manufacturer-specific PID library comes free with the hardware if I use the OBDLink app.

The field is "Status of the Shift Status / Lo or Hi". Not the most descriptive label for its function but I was able to confirm that this is what shows the current gear number.

 

[jseyfert3]

I kinda figured it would be there. Thanks for the update. I am planning on buying the OBDLink MX+ as it’s iPhone compatible and seems like it has more features than the cheap Bluetooth generic ones and Torque Pro (when using their app with the vehicle specific PIDs).

One thing I wanted to do was mount a tablet in my van and use the OBDLink app to display my tire pressures as measured by the TMPS system. On my van (2014) I know the data is the van data, but most adapters don’t have the right protocol to view this data, but the OBDLink MX+ and their app can.

 

[zolck510]

One thing I wanted to do was mount a tablet in my van and use the OBDLink app to display my tire pressures as measured by the TMPS system. On my van (2014) I know the data is the van data, but most adapters don’t have the right protocol to view this data, but the OBDLink MX+ and their app can.

I was actually just playing around with TPMS info (with MX+). There are four "ID # Tire Inflation Pressure" PIDs available, with the # being 1-4. I figured this is the TPMS-read tire pressure of the four tires. One weird thing for me was that three of them read ~55 psi and one read ~15 psi. I just had the tires rotated and refilled, so I know they should all be around 35 psi. I also confirmed with my manual gauge that they're all around 35 psi. I ran out of time to get to the bottom of this but it's something to keep in mind that they may not actually be accurate.

 

[BillG]

I thought TPMS sensors can only read when the wheels were turning?

 

[zolck510]

I thought TPMS sensors can only read when the wheels were turning?

I did not know that to be the case. I pulled up the PIDs and they gave back values so I took them to mean live readings.

 

[jseyfert3]

I thought TPMS sensors can only read when the wheels were turning?

They go to sleep when they stop moving to save battery. So yes, they won’t transmit pressure when stationary, unless you use a TPMS tool like my Ateq VT31 to trigger the sensors, which will wake them up and have them transmit one time.

 

[bencahill]

I have some experience with the OBDLink MX+ and TPMS. Here is what I can tell you.

From my readings comparing the MX+ with my tire pressure gauge, the MX+ reads about 13psi high. So if it's reading 55psi, that tire would be around 42psi. When the sensors are not reading (i.e. just turned van on), they report 14.5psi if I recall correctly.

From my experience, if I turn the van ON (engine not running) and start up the OBDLink app, the TPMS values will change from 14.5psi to an actual reading within 1-2 minutes, without starting or moving the van. At least that was the case with the sensors in my van previously (I assume they were Toyota sensors). I just changed out all 4 sensors for Autel MX-Sensor. It remains to be seen if the Autel's are any different.

 

[zolck510]

I just played around with MX+ a little bit more. My sensors read 55/55/55/15 with the van ON (engine not running). They remained at those values after starting, and even after driving. I increased the decimal place to 2 and they were the same -- e.g. exactly 55.12 psi and no change at all for at least 10 minutes. I was just running a short errand so I stopped paying attention once I arrived at Target and didn't look again on my way back. I think my TPMS sensors are just stuck at those values. This is not that big of a deal since I manually check my tire pressure fairly often. But something to keep in mind.

 

[jseyfert3]

Interesting. I feel like something isn't working right with the software reading those sensors from the OBD port. I would be the van itself knows the correct pressures, and if you lowered one 5 psi lower than the factory pressure (unless you re-programmed your TMPS to different than factory pressure) that you'd get a TMPS light.

 

[bencahill]

I would be interested to see what happens if you set the tire pressures differently, e.g. 35psi, 37psi, 39psi, and 41psi. I did something like that at one point to find out which tire was which so I could display them accurately in my phone app. That reminds me; I need to re-do that now that I have new TPMS sensors...

 

[floridanative]

I have an OBDLink MX+ which I'm trying to get it to read current transmission gear position with.
It has a built-in "Transmission Actual Gear Status" PID which does not seem to actually display any info.
I'd like to get something beyond the "P, R, N, D" status as in actual 1st, 2nd, 3rd gear etc.
Has anyone successfully done this before? It does not necessarily have to be with the OBDLink app since I do have a bluetooth reader and can use any other app. Thanks.

Yes, Car Scanner for iPhones shows the actual gear as well as if the torque converter is locked. Both available as included features with no programming or codes necessary.

Here’s my standard Car Scanner dashboard for the Sienna. The green arc shows the torque converter is locked and the number inside is the actual gear being used.

-Mike

 

[sixto]

Is this the free or paid version of Car Scanner? I have the free version and I can’t find that screen.

Sixto
‘04 LE FWD 203K miles

 

[floridanative]

Is this the free or paid version of Car Scanner? I have the free version and I can’t find that screen.

Sixto
‘04 LE FWD 203K miles

It’s the paid version. One time fee. I don’t remember which features were on free version and which were only on Pro version. The image is a customized dashboard. I thought dashboard was on free version, but maybe not all the sensors?

-Mike

 

[jseyfert3]

I have some experience with the OBDLink MX+ and TPMS. Here is what I can tell you.

From my readings comparing the MX+ with my tire pressure gauge, the MX+ reads about 13psi high. So if it's reading 55psi, that tire would be around 42psi. When the sensors are not reading (i.e. just turned van on), they report 14.5psi if I recall correctly.

From my experience, if I turn the van ON (engine not running) and start up the OBDLink app, the TPMS values will change from 14.5psi to an actual reading within 1-2 minutes, without starting or moving the van. At least that was the case with the sensors in my van previously (I assume they were Toyota sensors). I just changed out all 4 sensors for Autel MX-Sensor. It remains to be seen if the Autel's are any different.

I suspect it's exactly a 14.7 psi difference, and the pressure read from the MX+ is displaying psia, not psig, as 0 psia = -14.7 psig, and 0 psig = 14.7 psia. When most people say "psi" they are referring to "psig", or gauge pressure, which is the pressure difference from atmosphere to what you are reading. Psia, or absolute pressure, is offset by 14.7 psi because it's the pressure relative to a vacuum, and standard atmospheric pressure at sea level is 14.7 psia.

14.7 being the difference between TPMS reading and MX+ reading, may be slight variation between TPMS sensor and your own pressure gauge.

Yesterday I got my own MX+, and put two sensors on the app. I read 48.7 and 49.1 psi. I then used my Ateq VT31 tool to scan the sensors, and of the three working (I think the tire shop messed up one TPMS sensor) I got readings of 34.4, 34.6, and 34.0 psi.

48.7 - 14.7 - 34.0, and 49.1 - 14.7 = 34.4. This exactly lines up with two of my tire pressures, so I'm going to say this accounts for the MX+ pressure reading high. Now I just need to figure out how to subtract 14.7 from the tire pressure display in the OBDLink app.

 

[bencahill]

I suspect it's exactly a 14.7 psi difference, and the pressure read from the MX+ is displaying psia, not psig, as 0 psia = -14.7 psig, and 0 psig = 14.7 psia. When most people say "psi" they are referring to "psig", or gauge pressure, which is the pressure difference from atmosphere to what you are reading. Psia, or absolute pressure, is offset by 14.7 psi because it's the pressure relative to a vacuum, and standard atmospheric pressure at sea level is 14.7 psia.

Brilliant! Thanks for the info. I have an Autel TS-508, but I hadn't thought to compare its readings with the OBDLink MX+. I'll bet I will see the same as you. I will do that some time and report back.