Anyone have a conversion for volts to actual transmission temp?

[Siesta]

I thought I would be able to use my scanner to check my transmission temperature, which I need to figure out what the transmission oil level should be (I have one of those no-dipstick units they started in the 07's). So, I bought one of those "measuring tools" (dipstick) made for this purpose, and thought I was well on the way. Unfortunately, my Mucar OBDII reader only shows volts for transmission temperature and not the temperature itself, which seems odd. I'll also contact Mucar to see if they can help, but I thought I'd check here first. I know there are other ways to check pan temperature, but this would be so simple if it can be worked out.
thanks for any assistance,
Bob

 

[DadOSix]

I thought I would be able to use my scanner to check my transmission temperature, which I need to figure out what the transmission oil level should be (I have one of those no-dipstick units they started in the 07's). So, I bought one of those "measuring tools" (dipstick) made for this purpose, and thought I was well on the way. Unfortunately, my Mucar OBDII reader only shows volts for transmission temperature and not the temperature itself, which seems odd. I'll also contact Mucar to see if they can help, but I thought I'd check here first. I know there are other ways to check pan temperature, but this would be so simple if it can be worked out.
thanks for any assistance,
Bob

Bob '

how bout an inexpensive ir thermometer?

like a point and shoot laser type.

you could monitor the voltage on your scan tool as the jeep warms up, and as it changes, shoot a beam at the transmission pan. That temp might be close enough to work with.

 

[JeepJeepster]

There isn't a standard for volts to temp conversion, it could be anything. You would need to know the range for the sensor before you would know.

Using an infrared 'point and shoot' on the pan would work. I used a temp probe tapped to the 'measuring device' and pushed it down in the tube to check the temp... I didnt have an infrared gun at the time.

 

[Siesta]

Bob '

how bout an inexpensive ir thermometer?

like a point and shoot laser type.

you could monitor the voltage on your scan tool as the jeep warms up, and as it changes, shoot a beam at the transmission pan. That temp might be close enough to work with.

Thanks, I think that will be the way forward. Should be able to make a correlation graph this is close enough as you say.

 

[Siesta]

There isn't a standard for volts to temp conversion, it could be anything. You would need to know the range for the sensor before you would know.

Using an infrared 'point and shoot' on the pan would work. I used a temp probe tapped to the 'measuring device' and pushed it down in the tube to check the temp... I didnt have an infrared gun at the time.

I was assuming that the volts reading would be all that a Mopar diagnostic tool would need, and that my scanner (purportedly enhanced for TCM) would have been able to make the conversion. Apparently not.

 

[DadOSix]

42RLE factory trans temp sensor

www.jeepforum.com

not sure if this helps.

you may need to register there to see it.

 

[uss2defiant]

you can use this for temperature and manually measure the voltage to get your curve.

Transmission monitor KJ 3.7 42RLE PCI bus

I'm a hobby programmer and have written a windows program for the Jeep KJ 3.7 in the last 12 months. This program shows the status of a 42RLE transmission. After a few test drives it seems to work well. I have uploaded a video to YouTube which is showing such a test drive. The program runs on...

www.jeepkj.com

 

[DadOSix]

you can use this for temperature and manually measure the voltage to get your curve.

Transmission monitor KJ 3.7 42RLE PCI bus

I'm a hobby programmer and have written a windows program for the Jeep KJ 3.7 in the last 12 months. This program shows the status of a 42RLE transmission. After a few test drives it seems to work well. I have uploaded a video to YouTube which is showing such a test drive. The program runs on...

www.jeepkj.com

Never saw that!

 

[uss2defiant]

The OP recently reuploaded the program so it's accessible now. i couldn't get it to work on my end.

 

[Siesta]

42RLE factory trans temp sensor

www.jeepforum.com

not sure if this helps.

you may need to register there to see it.

Yes, I can see the dual temperature range graph okay, and it should do the trick..thanks!. There is some possible ambiguity if you don't warm up the engine enough, to know which of the two graph curves to use. But, I think if I get things fairly hot, at least to what is considered normal-hot by my manual (at least 180 deg F), then I would be squarely on the second curve of the graph. My scanner will give me a real-time temperature voltage, from which I can record the corresponding temperature off the graph. Then, I refer to the Fluid Fill versus Temperature graph that came with the 'measuring tool' (dipstick) that I bought, and read what the recommended fluid level is.............sheeeeeeesh. Progress, eh!?

 

[nbas]

If you have the '07 Liberty with CanBus, you will most probably be able to read the Transmission Temp from your phone with Torque App. It worked fine for a Jeep Wrangler 2008 of a friend of mine (42RLE with CanBus). If you have an earlier model without CanBus as I do, you will need the program (KJ TransMonitor) indicated by DadOSix.

 

[DadOSix]

Interested to see how this all plays out.

Another mopar we have is a 14 Town & Country with the 'mystery fluid - no dipstick ' thingy.

 

[Duster]

I agree this is all just very dang annoying. I understand why MFG's went to this. But for people with common sense it is annoying.

I figured out with a lot of pressure on me at the time that the oil dipstick is long enough to reach to check the trans fluid after you wipe it really well. Then you can measure the level with a school ruler in CM which is easily converted to MM. However the missing part is still the actual temperature even if you have a level chart. I just drove it around a good long time and considered it to be up to temperature. I got no idea what the temp actually is but know what the level is fully warmed up.

I'd rather just have an 06 dipstick and do it that way.