I am about to disconnect the battery to replace the engine fusebox. I thought I remember there being some issues with disconnecting and reconnecting a battery (besides losing presets etc.), but I can't seem to find anything regarding that. So, if there IS something, can someone give a shoutout to what that might be?

I have a nav unit in the car, upgraded rear heated seats (connected to the boot harness), upgraded low beam xenon lights. 2006 VDP

Thanks so much.

 

indi4ever, the biggest thing will be having to reset the auto up/down feature on the windows. But, that takes all of about 2 minutes to correct. After that, just make sure to connect up the battery posts correctly. If you wire them up backwards, there are stories of things going horribly wrong. But, you have to try pretty hard to do that since the battery terminals are different sizes and you have to do a lot to make one fit on the other.

 

Thermo, thanks. I'm pretty sure I can keep the terminals straight. Didn't know about the windows, so that's helpful. Found the fix.

 

The shop repair manual says you will be resetting your Engine control module. I think that means you have to go drive your car normally for a few miles to get it reprogrammed. There is a specific driving sequence described in the manual. The discussion is found under the battery replacement section of the manual.
P.

 

Also have your radio code to hand for re entering after reconnection!

 

You'll clear the learned values, zero the fuel trims, and clear all the OBD monitors (often used for smog tests).

If all is well these will relearn OK. If not, life on rare occasions is tough.

 

I thought I had the code on a nice Jaguar plastic card.
It was the wrong code but the main dealer supplied the correct code on proof of ownership.

 

One more minor thing, The wipers have a feature where they wipe one more time a few seconds later after you use the mist wipe, also in the manual.

 

Memory Savers that plug into the OBD2 port are so cheap and avoid all the resets/ relearning especially the radio code.
They are far more convenient that using the cigarette lighter or aux socket, remembering to advance the ignition key.
Instructions say use an external 12v source but other types say a 9V battery ( with the clip on terminals ) will work.

 

Unless the OBD power is switched (as I think you'll find it is), in which case such devices do nothing unless you leave the ignition on when disconnecting the battery - which you should not do.

 

What is and where is this signature line ? I will be replacing my battery soon ! 1998 XJ8L

 

Shido, if you mean adding a signature to your posts, click on your name in the upper right corner of the page. That will take you to your profile. From there you will be able to edit your information. Signature info is at the bottom of the "About Me" tab.

Note that this is the X-Type forum and you have an XJ. As I see from one of your other posts you are new and mention the forum is kind of overwhelming. There are a lot of similar Jaguar model types, but you will get used to it soon enough. If you have questions about your battery or run into any issues with it you will more likely get more and quicker respones pertinent to your situation in the correct forum. Good luck!