Hi All,

I have 3 x ELM327 bluetooth connectors. Each work great with my 2010 VW Golf. I used one of them on my XK8 last year and it worked really well. However, non of my devices will now connect the Jag but work on my Golf. The message: OBDII connected to the Samsung tablet but cannot connect to the car ECU. For additional information, I have always used the Torque Lite Diagnostic App. It just won't connect.
Having completed some "rustoration" work on the sills, I disconnected the ECUs in the engine bay before completing any MIG welding - I disconnected all of the connectors in case. I have since put everything back together and the plugs only fit in specific ECU sockets. I have double checked these and they all seem connected ok.

Any ideas anyone?

Thanks.

 

I assume that the car runs properly? I can't see why temporarily unplugging the ECU should make a difference although for welding you only need to disconnect the battery and many do not even do that. Have you tried connecting with both the engine running and not running?

Richard

 

First check the DLC (OBD socket) - that each wire goes where it should & no pin is loose/bent/etc.

If all OK, it's likely the software not doing the right thing.

In case it remembers how it talked to the other cars that would guarantee a fail as the Jag is not the same.

 

Thanks fellas. The strange thing is the ELM dongle worked fine when I used it last about 2 months ago! Zero fault codes so no issues!

 

Maybe the software saves some data such as where it found the PCM (which is unusual on the Jag).

You'd need to delete the data - once you find it...

Or maybe connect via some device you've not used before with the elm.

But FIRST - check the DLC!

 

I have managed to move the OBD2 port so it is more accessible. However, how the hell do you remove any of the pins? I have 4 that need further investigation but I cannot take them out.
Any google search brings up other OBD2 ports that have locking tabs etc - mine has none of these. the 5 on the right have white residue on them. Any ideas please how I can pull them out to check them?

 

OK fellas I sussed it !
There is a little locking window that locks all of the pins in place. I jimmied it up, placed a small screwdriver underneath the pi OBDn from the front and the pin came out! YAY!
Now onto fixing the pins and ensuring that they connect with the OBD2 dongle. I will post a photo tomorrow/

 

Well done....

 

OK, I went through every pin on the OBD2 port. Many were not catching my paper clip. All do now. Re-connected and still I cannot connect to the ECU via the OBD2 port. The connector plugs to the ECU have been disconnected and visually checked and all look good. I have this redundant connector though - anybody think it could be part of the problem??
jeez this is becoming very frustrating now as the poor idle is still there with the che k engine light and i cannot pull any codes.

 

One of the CATS suspension accelerometers is in the ECU compartment (mounted vertically on the side of the compartment) - that looks like the plug for it. Whether or not you have CATS, being unplugged does nothing to the network.

 

Thanks Dibbit.
As I am still not connecting to the ECU via ELM327 bluetooth (has power, connects between devices and WiFi), I am wondering if I can measure an electrical signal from the various input wires going to the OBD2 port? Surely one of these would indicate an issue and is the reason for no ECU connection? If I could find that maybe I could trace the wire back etc/ continuety and see if it is actually the ECU or a wire. The car still has a misfire, it drives etc but definitely a misfire. The ELM 327/ Samsung tablet combo works perfectly on two of my other cars so that is not the problem.

 

A really simple test you can do is measure the resistance across the CAN network, which may or may not be relevant to your issue:-

https://www.jaguarforums.com/forum/x...ooting-144485/.

Also bear in mind just because your scanner works on another car, doesn't mean it will work on your Jaguar. I have two different bluetooth OBD dongles, one works on the Jaguar, the other doesn't and I have no idea why. And don't forget the ignition needs to be on for the scanner to connect and make sure Torque isn't set to just look for one protocol.

Have a look at this thread which explains why on early cars you need to jumper two connections to get the proper wakeup signal to the reader, again, maybe this is related to your issue:-

https://www.jaguarforums.com/forum/x...ooting-144485/