This is a feature that most Jeep owners would like to have. It is also about 50% of the reason I bought the app. The data is available because there are some apps and devices that can show it.

If there’s something I can do to assist I would be glad to help. I will be trying the above info later today when I have access to my jeep.

Thank you for the update!

from that, the PID would be:

22B010
ECU: 7E0 (try this or ‘Auto’ and blank)
Equation: not sure – likely: ((A*256)+B) * 0.25

The wake up ECU – may be needed, though not entirely sure about the PID of ‘1092’ (mode 10, pid 92). My notes say that’s a diagnostic ‘enable’ message so don’t be driving the vehicle when you send this request. I would see what the 22B010 PID gives in response data before trying the ‘1092’ mode/pid.

The ECU in a Merc I have access to is basically a chrysler ecu, so the PIDs may be similar. I’ve not tried 22B010 yet so will have a play myself with this and see if I get a response.

I’ve now got suspect PIDs (for various chrysler vehicles of:

2103
2130
22B010

Still need scaling and units for the equations though (if the above are indeed trans fluid temperatures).

An relatively easy way to try to work these out are (I’m using this method to work out TFT on a Dodge):

1) get the PID data from cold (leave the vehicle overnight) and measure the outside temp
2) drive around a bit, get it warm and take another reading.
3) spend time with a calculator trying to work it out from the (hopeful) differences between the PIDs

other methods could involve comparing readings against other scantools and working out if anything matches from that.

You may need to create a PID of ‘1092’ (mode 10, pid 92) as well (and have that display visible. Just have ‘a’ as the equation for that display and anything else should be fine)

With that display visible on the screen as well as the trans temp, then things may start to show stuff for the 220b10 pid or others. I would test myself but I don’t have access to the vehicles (apart from the merc)

The 1092 is an ‘enable’ , similar to 3E / 3F for other vehicles. Make sure your vehicle is parked and ‘safe’ before trying this though!

hm, ok, it may not be that one for your type of vehicle. ‘3E01’ may be another such keepalive instead of 1092, possibly with the header for that set to ‘7DF’

PID: 3E01
Header: 7DF

I tried the 3e01 PID with A in the equation. No check engine light this time. Still no reading on the PIDs. I’m going to give it another try tomorrow. Thanks for the help with this. Hopefully we are getting closer.

You’ll need to experiment with the equation (in particular the variables based on the response) – unfortunately I don’t have a jeep to be able to play with

If you are getting a response for the PIDs, then that is good – get the response that is working for the PIDs from cold(in the morning for example), and also from Hot and you should then be able to work out the temperature if it’s there

Ok. I think I have really good news. I have a decent reading. The 1092 pid worked, but kept setting off my ABS and other lights the longer it was active. The 3E01 Pid wakes up the ECU and doesn’t trigger any lights. I used the initial 22b010 PID and get a good reading with the equation of just A. I’m going to run a few tests in the next couple days and post my findings. Not sure what was going on with my last tests, but everything seems to work ok now.

I am looking forward to testing this. Could you please let me know the specific settings i need to insert to add this pid. Thx in advance.

Hi

That’s excellent news – looks like the wakeup is the key.

It would be very interesting to see if the transmission temperature matches the outside temperature after you have left the vehicle overnight (that way we can be more sure there’s not a conversion required for this) – if you could confirm this then it would be very helpful (as unfortunatley I don’t have a jeep to play with at the moment!)