In that jagxk2003 1.pdf file posted way above, pages 17-23 give locations of power distribution, grounds, modules...

Seems like your Jag is still pretty clean, solid and corrosion free, unlike a lot of 20 year old rust bucket I deal with in salty Michigan. Fortunately, all our Jags are from the south.

 

Lookn at them specific codes,,,

The BPM must have a sufficient ground or it will create all kinds of havoc and great mysteries...across multiple systems.

Bolting the BPM to the body of the car completes grounds for many systems.

If you are a contortionist you MIGHT be able to get at the bolts that hold the BPM to the underside of the dash of the RH foot well. If you look at the ED there are also wired grounds that come out of the loom/connector plug of the BPM. Anywho

Get to the BPM under the dash. Remove the glovebox. Easy. Get in there and make sure that the contact points (the nuts on the BPM fixed bolts) are tight and clean. MAKE a redundant ground using 2 eyelet connectors and good wire and place the eyelets under each of the two nuts and bolts and string it out to the body. Good ground.

Try again.

There are negative ground posts (I believe) behind BOTH forward kick panels in the foot wells. The vertical small ones.

I can't remember - is this the car that had that unusual corrosion growing on the OBD connection port?

 

Hello
I did a hard reset and checked and cleaned several grounds. See attached document. The grounds with X on them have been found and cleaned. The ones with a circle around them I cannot yet find despite having taken off every cover. I would appreciate any hints on finding them. The ones with nothing next to them I have not checked or looked for yet.
I have only driven it about 10 miles so far. It ran fine except for one time pulling away from a stop sign, it jerked into gear a little. Well, the check engine light came on but I expected that as there is possibly a small leak in the evaporative emissions system that I need to smoke test I guess to find it.

No corrosion on the OBD port or any other place I have checked.
I have yet to find the BPM but will try to find it and add the suggested ground wire.

 

if this was a rust bucket, I would junk it. These cars have no real value and rust repair is expensive if you pay someone and while I can do rust repair, I have too many other projects to do. A friend up in your area does Alfas and what we call rusty here, he calls pretty clean.😂

 

Mine has value,,, to meeeeee 😊

 

I just bought and installed it in my 2003 XK8. Frankly, I was impressed by the construction of the assembly but cannot speak to the quality of the motor.I let you know in a year or so.
Paul O. (Paul1940)

 

Ha! And it's working/in service? Good to know.

I'm interested in its working over time, as well! Please keep us updated. Mine is sitting in a bag on a shelf and to a degree (ya know?) it provides a little reassurance, in a world that ain't always so reassuring, lol...

 

I get it.
I have had a few like that. Fun to restore but no expectations of a return on investment

 

I guess no one can tell me where those grounds are under the hood that I cannot find?

 

Update: I took the car for a 65 mile trip today after accessing the BPM and adding the suggested additional grounds.
It performed well but after returning, I read the codes and the same ones are still active. See those highlighted in yellow on the attached sheet. Still trying to locate two grounds under the hood as mentioned in a previous post.
Any more ideas?
Thanks

 

Were the codes cleared?

 

nope. Pretty much the same ones still there.

 

After driving a total of 170 miles, I have the same codes plus one for a incorrect gear ratio when It sqwuaked once. I hate that gearbox!

 

Any ideas? Any one? Bueller?

 

Since it rolls over, it appears the problem is not in the key, immobilizer, instrument cluster nor BPM. ECM would be obvious suspect. I would open the cover over the ECM and then disconnect each connector, examine them carefully, maybe blow them out with air, then reconnect. I can't tell you how many times I've disconnected/reconnected ribbon cables on robots to bring them back to life.

One other area to check is the wiring to inertia switch. Its job is to shut the engine down. OBD codes do not inhibit running but the inertia switch can. IF you do have fuel pressure, the switch is grounding the BPM and relays appropriately.

I pointed out fabricating a little harness and converting my cell phone into a rudimentary oscilloscope in "NO CRANK mystery & misery" and then slipped the needle probe into connectors to coils, ECM and elsewhere looking for signals. That removes a lot of the guesswork.

 

By CLEAR the codes I meant use the OBD device to hard CLEAR them from the ECU,,, drive, and see which reappear...

Please LIST the codes you are seeing AFTER CLEARING and driving, if you can....

 

that is what I have done (twice)and they come right back.
to clarify, the codes for the BPM, DDM and PDM will not clear

 

I once had trouble getting a code to clear. I didn’t have any symptoms of anything wrong with the car’s driving abilities, just a code that wouldn’t go away. Can’t remember the specific code number.

after removing the code with my code reader it would stay off for about 60 seconds, then reappear.

Finally I thought to clear the code, and immediately turn off the engine before it “reappeared”. Then I did the full hard reset routine. I started the car, and completed the usual list of things needing to be re-done after the hard reset, like the windows, etc.

Then checked for any codes. There weren’t any. Turning off the engine immediately after Coker clearing, and then performing the hard reset did the trick.

don’t know if this would be of any use to the OP. Just mentioning how screwy a fix can be sometimes.

Z

 

All info and ideas are appreciated. I have done a couple of hard resets. Tried several times to clear the codes that don’t want to clear.

 

Some of the codes on the PDF are well known with well known fixes - just fix them!

Worry about others after that.

BTW a lot of people won't bother to open a PDF. Generally I don't...