Hi and thank you soo much for your reply

Yes the can system goes shut after 15 mins like all the rest of the electrical system of the car.
I saw the electrical diagram with all the infos on this chip and there're 4 way to link it on the car, but on xk8 works just on can system.
I guess that if in the fuse are box close to the obd port (rearside) would be a +12v power source that doesnt shut it wouldnt be a problem because if the other pins are linked at the can system the chip is autodesigned to go on sleep mode and wont drain the battery at all.
But looking at the xk8 electrical diagram i didnt find a +12v connection close there where i should link the chip power... maybe you know where

The problem like i told you is that volo vp12, i was so so so sceptical when i bought it few days ago, requires about 150 miles to full calibrate and give full performance, yesterday i drove no stop for 350km and i must say that this chip even if is not expensive really works, and im the first to dont believe in that, so i asked my girlfriend (she didnt know about it) to come with me on the car for a tour, and she asked me, did you do something to the car ? I feel it different, is more fast.
So is not psyco effect , i dont know how and why, but the vp12 works.
After i recovered the car at the restaurant for 1 hour, i went home and i unfortunately saw that chip was recalibrating, so it lost power.
Thats a big **** because initial calibration last 2 minutes and you cant move the car and even touch any pedal, and i tried to give full throttle immediately after and like i was afraid it lost memory and lost any effect.
At first i cant wait 2 minutes stopped like a stupid everytime i switch on the car, and at second is very hard that i make more than 100 miles no stop during a normal day, so i cant use the chip that i wanna use because works fine.
Linked to the can with other cables and with the +12v linked to something that remains "alive" in the car when is switched off, the chip will switch on sleep mode and wont loose memory.......

 

Is your chip power connected to pin 16 of the OBD port? This is direct battery power and DOES NOT go away after 15 minutes.

If this is how you are connected, then the problem IS NOT related to the power wire going to sleep, it is related to the CAN bus going to sleep. Like I said before, if you then do someting to keep th CAN bus awake, your battery will drain too quickly.

 

Hi guys thank you so much for all your replies !!!
I solved the problem, the 16 pin doesnt go "to sleep"
To dont loose memory on the chip, is necessary to turn ignition (like check engine position) for 2 seconds till the chip goes online and after turn on the car.
Everything is fine guys
Thanks again for your support

Ciaoooooo
Luca

 

SORRY FOR THE BOOK:

I figured I should update this thread since I still haven't got this problem fixed. Hopefully this will help somebody in the future (if I ever get it fixed)... As everybody knows that reads this thread I can not read my the OBD II computer. I started out with a check engine light, restricted performance message, gear box fault message, airbag light and a problem where when I used my turn signal at night all my interior dash lights would flicker. The dash/signal problem is now fixed it was a wire in the turn signal switch that I soldered back. The airbag light is now fixed I replaced the airbag module by the glove box. The check engine light, restricted performance and gear box fault were all caused by a problem inside the gear box a little plastic piece had broken off. I JB Welded that piece back on and bam every light went off and has not returned in 4000+ miles.

So here is the issue my vehicle it runs great just like a Jag XKR should no messages no lights no problem. BUT I still can't read the OBD II so if I ever have a problem (check engine light illuminates) I have to diagnose and fix the problem without being able to read the computer.


My independent mechanic checked the wiring cleaned up a few connections thought the ECU needed to be reflashed which the dealer would have to do because he doesn't have the right equipment...

Checkered Flag Jaguar I quote "Performed diagnostic scan. Found that the ECU, Restraint Module, Instrument Cluster, Climate Control Module are off line and ABS module is showing as faulty. Started with checking power, grounds and can bus connections at ECU, all good. Checked some ECU voltage outputs to sensors, no voltage was found. Any further diag will have to start with replacement of ECU. SUMMARY: We found the ECU not responding, running in fail-safe." This was before I fixed all of my problems myself so idk if they would still get that many faults. They (Checkered Flag Jaguar) wanted to charge $6000 to replace my ECU . I purchased a used ECU with the correct VCATS to replace my old ECU for $500. Time to get the immobilization procedure done! I took it to a different Jag dealership because I was not happy with Checkered Flags level of service...

Browns Jaguar diagnosed the problem as a bad instrument cluster, they told me they couldn't do the immobilization procedure on the new ECU because the instrument cluster was bad. Okay no problem I picked up the vehicle and bought TWO replacement instrument clusters and an additional replacement ECU (just in case). While I had the vehicle I figured out all my warning lights were due to the plastic piece that had broken off in the gear box. Fixed that and returned the vehicle to Browns Jag with no warning lights or messages of any kind + 2 replacement clusters and 2 ECUs. Here is the kicker if you actually read this whole thing.......

The car was at Browns Jaguar for 2 MONTHS before I asked what was going on. They said we don't know we can't figure it out you might as well pick it up! What am I supposed to do if JAG can't even figure out what's wrong with my car? All I want to do is be able to read my OBD II like I used to with no problems.

 

i invite you to take a drive up to Northern VA on a nice weekend day this spring and we can get a scope on it and try to figure out what is going on.

 

I appreciate it! I didn't realize you were only a couple of hours away. I'll PM you.

 

I've got to get my 1997 XK8 smogged here in Calif not later than middle of July. I've run into this same OBD ii 'can't read' issue as described in this post. Has this been resolved? I've checked all fuses and they're fine but there's no readings from the OBD port. Car passes smog otherwise and runs great. I'm scared I'll be scraping a beautiful Jag!!!

HELP please!

 

Haven't resolved it yet! Let's hope this isn't a scrap Jag problem!!

I was supposed to meet up with WhiteXKR to help me diagnose it last summer but I had another hydraulic hose failure (fixed), restricted performance (fixed, very hard to diagnose without OBD II but I figured it out), and broken fog light (almost fixed) all around the same time. In a few days it should be back in perfect condition and hopefully WhiteXKR will still be able to meet up with me about the OBD issue....

 

Good luck - it can't be more than something "simple" (once found).

 

I sure hope that something simple turns up or one beautiful XK8 is heading for scrap!

 

Just sell to someone who has a clue with electrics.

 

I got LUCKY!!

It turned out the smog station's device was the problem. Took it to my local
Jag mech that's always worked on it and he threw on his OBD reader and it read okay. Took it to another smog station of his choice and it read fine.

I'm breathing easier again!

 

I'm having a similar problem with a no read on OBDII port getting a linking error. Did you ever figure out what the problem was? When you replaced your ecu did you have a problem with the VIN not matching?

 

Yes I did! The VIN doesn't have to match, I purchased a used ECU from eBay with the same part number and VCATS number to replace the original. I don't think the VCATS number had to match but it was available so I purchased it.

Tim from Autoecu.com solved the problem for me, he was great and worked with me to figure it out... Autoecu said the original ECU needed a "complete overhaul", we tried that but it didn't work, I still had the same issue after the overhaul. On eBay I purchased a used ECU, I sent the used/eBay ECU and the original/overhauled ECU back to Autoecu. Autoecu flashed the vehicle data from the original/overhauled ECU to the used/eBay ECU and rebuilt it for me. No, they didn't charge me anything extra, all covered under warranty! They sent it back, I installed it in the car (it only takes 5mins) and I could read my vehicle again!!!!

I'm in no way affiliated with Autoecu, in fact I tried another ECU repair company before them and they weren't able to solve the problem. I also took it to 2 Jaguar dealerships and 1 independent mechanic that wasn't able to solve the problem. Checkered Flag Jaguar in Virginia Beach is quite possibly the worst dealership I have ever dealt with, they told me only a new ECU would work and it would cost over $6000. Browns Jaguar in Richmond kept it for over 2 months, they told me they couldn't figure out what was wrong and to come pick it up.

 

Sorry for my ignoramousness, did the ebay ecu need to be 'flashed' for the security software to mate with the key?

 

No problem, it took me probably 2 years to figure out this problem.... feel free to ask questions.

Yes it did have to be flashed. I thought by purchasing an ECU with the same part number and VCATS number that it wouldn't have to be flashed. I was wrong! The car would not turn over until the vehicle data was transferred/flashed from the original, probably because of the vehicle security. If I had somebody more affordable then Jaguar that could have completed the security immobilization procedure I think the car would have run without the need to flash/transfer the vehicle data.

If you purchase a ECU with the incorrect VCATS number, I think the vehicle data would have to be transferred/flashed to overwrite the wrong VCATS. From my understanding an immobilization procedure will not work because of the mismatched VCATS.

 

Hi seawind,
interesting post glad you got sorted, I have a similar problem , car is running ok (2000 my XKR) tried official jag diagnostics machine and it could not read all the live data, some info I could get but not all, as car is running ok thought no more about it till your post, so your problem was a bad ECU was it or have I read it wrong.
regards
RRosscoe

 

Yes my problem was a bad ECU! No signs of damage to the ECU once opened up. Two reputable ECU repair companies tried to repair it with no luck, so I had to replace it and have the vehicle data transferred, thanks Autoecu!

My cheap OBDII could not read the ECU, when it normally does with no problems. The official Jaguar tool pulled a p0117, p1111, p1260, p0174, p0171, p0400, p1638, and p1642. I believe some of those codes were unrelated problems I was having with the vehicle at the time. The instrument pack gave back a [ERR0xb] Communications Failure, which according to the official Jaguar description is a CAN link engine control module/instrument cluster circuit/network malfunction. After replacing the instrument cluster and checking the wiring with no change, I narrowed it down to the ECU which fixed the problem.

 

Well looks likeI will be on the lookout for a replacement "spare " ECU just in case mine gives up the ghost.
Thanks for the info
RRosscoe

 

hi SeaWind i read all your posts about cant scan car .do you know if the ecm has the same vin #as the car ? also ware is AUTOECU i might need to send mine to them . i got some info off a snapon scan tool but not shure if its valid . and dont know mutch about this car .barley had it for 2 weeks .boght car out of storage for 4 yrs . hard to start 'roughf idle . scan tool showd -24 timing .idont know if it would start off that much .saw a thread on timing chain problems going to check it out thanks for the info and time .dan l