Hi, I have inherited 1997 XK8 converitble (74,500 miles) and have been slowly restoring it.

All New suspenbsion, rebuilt differential, etc.
Has been running well except for something that started last year.
Was running along fine and then got engine perf warning and car went into limp mode. Ran rough and stalled. Finally got it running after 5-6 tries, reved it to 3000 and it suddly cleared up. Drove 3 miles home fine, and put my reader on it. No codes.
Drove another 100 miles end of season no problem.
After getting it our of storage this year, had oil changed no problems. However after I washed it got ready to drive and same thing. This time I threw my code reader on it and got the the codes Ignition coli primary circut failure codes P0351, P0354, P0356, and I believe P0357. I also got the P1367 Ignition systems failure group 1.

In reasearching it first appeared likley that it was either the Ignition amp module for group 1 or the ECM. However I also noticed some posts on the forum to check the battery. I did that and my charger only showed it to be 50% charged. I put the tender/charger on it and charged it up to 100% drove it for 45 minutes (32 miles) including several stops and starts. Ran flawlessly. Checked codes, all gone except 1111 System pass. My questions.

1. How likley is it my problem is the battery?
2. When it is the Ignition amp module or ECM are these problems typically intermitent or once they start they manifest until fixed?
I noticed after driving yesterday when it checked the charge it was between 75-100%. I did start and stop several times, but that drop surprised me. I am thinking battery (4 yrs old) but also wondering about alternator
3. The volt meter in the car show solid 13 when running. If the alternator wasn't putting out enough should I expect to see that on the volt meter or via a warning light or code?

Where I am its really hard to get service, all my local guys have retired and I have to go 100-150 miles. So the more I can diagnose myself, the better.
Thanks.

 

You know it’s the battery.

when you get a new one, get a quality AGM battery and keep a v b artery tender on it whenever the car is not being driven overnight or longer.

NOCO Genius, CTEK, and Delran Battery Tender + are the ones they have worked very well for forum members, especially the first two mentioned.


Z

I would like to see 14v unless the battery has just been fully charged, then maybe a little less. My 2002 XKR always is at 13.9-14.7v rain or shine.

Yes, your alternator might be at fault too, but the smart money says get a battery first.

 

I charged the battery to 100% on my tneder. Took it out. First 10 miles was fine. Then on way home it kept switching between engine fault/lowered perf limp mode and normal. It would fault, run like that for 30 sec, and be fine for two minutes. Finally the last 3 miles it was ok. Checked codes, same ones back.

Checked the battery, it was down between 75-100% and fullly charged up within 25 min. I am going to let it sit for a day to see how much it drops.

a couple more questions.

1. If the alternator is not charging properly, would that be expected to throw a code?
2. On battery replacement I have seen some discussion on the forum regarding length of time required for powerdrain after power disconnect.

Does this mean I should wait 60 minutes after battery disconnect to swap new onew in? or that I should make sure the battery is swapped within 60 minutes from disconnect or does it not matter?

Also, is there any special reset proceedure I ned to follow after battery swap?

Thanks.

 

If the alternator is not charging the battery - you will get all kinds of errors and eventually a complete power loss - which sucks when you're driving down the interstate at 70mph

 

Ok, so seems less likely its the alternator I lost no other power, so more likley the battery then?

 

Those shut-down values have no bearing on the battery swap procedure. Simply remove the old battery and replace it with the new one which you should fully charge on the bench before doing the swap. The swap will only take 5 minutes which is fine. You might need the battery vent or might not .... it depends upon the old and new battery construction.

You will need to reset the windows and re-enter the radio code but, on older cars like the XK8, that's it. I personally attach a temporary battery on flying cables when I do a battery change to avoid having to do any resets but, unless you have suitable equipment, I wouldn't bother as it doesn't really add anything.

Generally speaking, if you can charge a large battery from that level of discharge in 25 minutes with a home battery charger, then the battery is definitely shot. It should take several hours from a normal level of discharge even using a 10A charger.

Richard

 

Thanks for the battery swap info.

I think I may have not been clear. The level of charge I saw was 75-100% of a full charge (my tender only lists 4 bands by 25% intervals) not down 75%. My battery tender is a 4 amp model that slows charging to a trickle in the last 25%. I am going to see what state the battery is in after sitting in the car for a day.

a CTEK battery tender was recomended. I see that one model has both battery and alternator testing routines. Has anyone tried these?

 

Hi JAGQZMAN,

In addition to the great input you have already received, I would strongly recommend that you test your alternator. You can do rudimentary tests yourself with a good multimeter. There are instructive videos on YouTube like the one below. Or, have the alternator tested with a good professional analyzer. It may be that your alternator output voltage is low or is producing high AC ripple, or has an intermittent fault in the voltage regulator or rectifier. Also, check your accessory drive belt for excessive wear or glazing.


Another very common problem with the charging system in our Jaguars is corrosion on some or all of the many battery power and ground connections in the vehicle. Every few years at tune-up time I go through the car, starting at the battery, and clean all the connections: battery cable terminals and battery posts, battery ground cable connection to the body, disassemble the high-power protection module on the trunk/boot bulkhead foreward of the battery/spare tire (the plastic box with the large megafuses), the battery power connections to the fuseboxes, the false bulkhead in the engine bay, the connections at the starter and alternator, both ends of the engine ground strap, etc. I also clean as many of the Engine Management System ground points as I can access. Just a little corrosion adds considerable resistance to the electrical circuits, and the resistance at multiple connections is cumulative.

To clean the connections (with the battery disconnected), I use a small brass-bristle brush, battery terminal brush, and a good zero-residue electronic contact spray cleaner (I use CRC QD Electronic Cleaner). Allow the megafuses, cable ring terminals, nuts, washers and threaded studs to dry, or dry with compressed air, then reassemble. Do not use sandpaper on these connections because scratches create paths for moisture to wick into the joint and promote future corrosion. A gas-tight connection is crucial, but you also don't want to over-tighten the nuts because it is easy to damage the threaded studs or even to break them off of the body, fuse box, etc.

You can locate all these connections on diagrams in the Electrical Guide, which you can download at the link below:

Jaguar X100 Electrical Guide 1997

Cheers,

Don

 

Thanks for all the great info. In looking into replacing the battery, I noticed a cable that was not attached to anything. From looking at the witing diagram I am thinkling it may be an accessory connector? Any other thoughts

 

I seem to recall that that connector is part of the Transit Isolation Device circuit, so it should not connect to anything now.

Cheers,

Don