Hi does anyone know if the 93 XJ40 has an OBD port?

I’ve noticed the ECU is reprogrammable, I was wondering if or where the port was to connect to it was located in the car.
under the drivers side dash. I also discovered 2 or 3 unused connectors and wondered if 1 was the OBD port.
the other question I have is my car came with central locking but no key fob. if I was to connect a key fob should I be running wires to the drivers door or some place else.

Not reprogrammable really, but there are some market specific settings you can change with a PDU “Portable Diagnostic Unit”. The connectors are not a single point… like the ECU uses a break out box, the ac used another, the ABS uses a third unit. Despite name it is not portable, since it’s 6 feet long and bolted to the wall. If you’re anywhere near New Hampshire USA you’re welcome to try mine.

Not really sure what you meant by a break out box… & sorry im in a little town south of Auckland in New Zealand.

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A break out box in this case means a special connector that goes between the ECU and the ECU plug that allows the PDU to tap into every wire going to ECU. You unplug the the ECU, plug break out box into ECU, and plug the car wiring harness into break out box. That allows you to put a the PDU in-line between car harness and car ECU and read the signals. It’s ridiculously old fashioned and nothing like ODB.

What is wrong with your car again? Maybe we can figure out a way to fix your issue without using these tools.

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The OBD port (DATA LINK CONNECTOR) on the 1993/94 cars is below battery tray.

Look at Electrical Guide S65_93.pdf

Just understand that there is a huge difference between OBD and OBDII. When people think of OBD, they really mean OBDII like a modern car. X300 and up have OBDII. The 1995 US cars received more functionality with a recall but it was required for cars 1996 and later.

The 1988 sedans and XJS were the first cars to actually communicate with a device. The first one I used was PDU because I did not work at the dealer when ‘PINOCCHIO’ (JDS) was introduced. They called the first unit that because it always stated that the engine harness needed to be replaced.

Finally Jaguar told everyone to STOP CHANGING THE HARNESS!

There are 2 or 3 different connectors for the OBD system on the early cars.

My 1992 XJ6 had a round PM4 plug under the battery in the engine compartment for communication.

Different locations and connectors for different cars.