1998 XJR. I need to check/read the transmission temperature. The OBD reader I have is not capable of that feature. From what I can determine from other threads, it looks like reading the transmission temp requires more of a “deep dive” than a cheap reader can do.

Can anyone tell me what I need? Brand, model, or app name, etc. would be helpful. Or tell me if I have to take it to a shop to have it done. Thank you.

 

Save all that bother and you can safely place your hand on the auto sump
when it feels quite warm without being hot.
Or you can use a digital thermometer (laser type)
Or you can use a digital cooking thermometer you can insert in the oil through
plug hole.....48-53 deg.C....and your'e pretty close ;O))

 

The gearbox temp is on the CAN bus BUT..............
The selector must be in Drive or Reverse, otherwise the engine temp is substituted. (see TSB 307-06)

bob

 

My ignorance here is fairly acute so please type slowly. Haha. I apparently need a reader that is capable of reading the CAN bus, and apparently mine is not capable of that. Does the device have to be Jaguar specific, or can I go to a local shop that has never seen a Jaguar before, have them hook up their reader, and tell me the temp? I see in the TSB under "Action", it describes how to access the proper menu item to get the reading. Will any reader capable of seeing the CAN bus be able to extract the reading, or does it have to be Jaguar specific? This is helpful, thank you!

 

Specialist, not cheap, device only. Why do you NEED to do this?

 

I'm still chasing down a shifting issue that I've been working on for a couple years. You can look up other threads I've posted with questions/updates over the last couple years to get a feel for the issue, but long story short, after a long drive on a hot day followed by start/stop driving, the transmission refuses to upshift until between 3,000 and 4,000 rpm.

The threads will show you a hundred things I've tried, from my own research and from advice from the forum. No dice. I've never seen a high transmission temp warning, and supposedly the tranny shop checked the temp on a hot day a year ago, but I'm revisiting everything to try and pin down the problem.

I'm now thinking that MAYBE a cooler line is partially blocked, so on a super hot day, after a LONG drive (2 hours), the temp eventually gets too high and causes it to shift funny. Again, I've never seen a tranny temp warning light, but here we are - it has to be temperature related and this is something that I have not physically put my own hands on to test. I have only the word of the shop from a year ago. Maybe they didn't get it hot enough before they tested it, despite my specific instructions on how to replicate the problem.

In a nutshell, that's what I'm doing. So I need a Jag specialist with the correct machine, is that what you mean?

 

I have an Autel MX808. It reads everything, with live data from the ECU and TCU; $385 from JB Tools.

 

I have a Foxwell NT 510 with the Jag / Land Rover module (as well as GM & BMW). Great price point and excellent for my BMW and GM needs where it does all I've ever needed and more. Reads most things, but only caution is on the Jag the module is not able to identify the car automatically as it seems to only be able to read for ~2000 and later model years and some functions on my car are hit and miss - it seems the Jag s/w was changed perhaps with the intro of the AJ27 engine??. On my 98, I can operate the transmission solenoids and do a few other transmission things, but can't recall if it reads the trans temp. However, I have the ZF box, not the Mercedes box found in the XJR, so it may be a different matter for your car.

 

I use an infrared thermometer similar to medical use thermometer ie hand held put in your ear type
Does the job. Wrap a cotton rag around exhaust to avoid burns fitting plug into transmission whe correct filling achieved

 

Do you think it will read the transmission temp on my 1998 XJR? The car is OBD II compliant, but I don’t know if that means it will work. Thanks for the suggestion.

 

Yes; It reads mine off an '02 XJR, and we have the same MB 722.6 transmission. It also reads the ABS and told me the right front wheel sensor was out. Cleaned it and it works again.