I’m having a problem reading the coolant temperature on my car (Jaguar XKR 2001) with Torque – no value is received.

I get the same issue using my PC instead of Torque and I can solve it by turning the headers on with AT H1 (without headers on the data string returned is missing a couple of characters and is invalid).

This is the only PID affected – all the others work fine. I’ve looked through all the settings on Torque and can’t find any way to turn the headers on, or insert an AT H1 command at startup.

Is there a way to do this on Torque?

Edited to add: –

“Always use OBD Headers” in Special Settings doesn’t seem to do anything.

Editing the PID and adding ATH1 as a diagnostic start command seems to work when I press the TEST button, but doesn’t work when using that edited PID on the real-time display.

Thanks. Where do I find the init string? The closest I can find is in Vehicle Profile – Custom Configuration String – that is sent before connection. I tried adding it there but it didn’t work.

>only PID affected?

Correct.

It’s a standard PID 0105, but instead of returning 4105… the second byte is either corrupted or missing. For example it might return 4138… where 0x38 is the temperature value. ATH1 makes it respond correctly, ie 410538…

Thanks for that. Its a nice workaround – its not going to be 100% reliable, because that second byte (that should be 0x05) sometimes comes back corrupted rather than missing, but at least I can get a working temp. gauge most of the time, so that’s a huge improvement.

OBD Fusion displays the temperature no problem with the same OBD adaptor, so I’m guessing they have H1 set as default – so I would still like to be able to do that on Torque if anyone knows how?

Thanks for that suggestion. Having ATH1 as the Diagnostic start command works with R5-40 as the equation.

The response (with ATH1) is (eg):

48 6B 11 41 05 6E 78

So I now get the correct response (41 05). The 6E is the engine temp which is the correct value. I don’t know what the 78 is on the end.

However I need to test this some more as I think perhaps some of the other PIDs are now misbehaving – I also tried adding ATH0 as the Diagnostic stop command, but again wasn’t sure about the other PIDs.

Incidentally the module addresses should be:-
Request 0x7E8
Response 0x7EC

Thanks for the explanation – that’s really useful.