Hi
Tried starting the jag today, all the lights came on but all I got on turning the key was a click. It's been running fine and the engine hasn't missed a beat. I've tried it a few times and every now and again a PECUS t fault flashes up (not every time).
Does anyone have any ideas as to the problem and is the PECUS fault causing the motor not to turn over or is it a by-product of some other fault?
I realise faults are difficult to diagnose like this but any suggestions or previous experiences would be gratefully recieved.

Many thanks

 

When's the last time it started and ran properly?

 

if it just clicks the battery is most probbably low on charge

 

Use the search at the top and you will get all the information you will want to see. I am not familiar with this fault but it refers to the pecus is a programming fault and could be related to your no start. Was this car in storage? Give us a little more info. We are in a box with no windows and we cannot see you.

 

Most likely battery....
Had exact same thing (minus the PECUS message ) happened to me.
Had my 99VDP for couple of months, no problems no start hiccups, BUT from time to time I'd get a message that one of my lights was out, even though all worked fine. Quick ON/OFF with the light switch and the message would go away. One night I went to work out, and on the way back, I get in the car, turn the key, dash lights come on, headlights come on, but engine wont turn, just clicks. Was sitting there for a couple minutes trying and trying, but nothing but clicks from engine. Had my scared thinking something MAJOR broke. I mean, all light come on normal, but cant start... Thankfully some guy saw me having problems and offered to "jump-start". Sure enough, as soon as I got "juice" the engine cranked like nothing ever happed... The whole "check light bulb" was most likely a side effect of the low battery...

 

I'll try the battery tomorrow. I last used it on sat (about 48 hours ago) and it was fine. Perhaps interior light was left on or something. Any idea what the voltage on the battery should be at rest? Also, I've seen a few threads where people have been reluctant to disconnect the battery incase of memory loss. I have the stereo code and I'm not bothered about the seat memory etc, but are there any other problems ie. ECU settings, remote fob etc.
Thanks for the great response, really helpful

 

Try Jumping the car withour dis-connecting the battery !

 

The voltage reading will not give you an accurate status of the battery. Mine (when it "died") was reading 12.5+ V. It's how much that voltage drops under load, that makes the difference.
Aloso, I have disconnected the battery on my 99VDP for 30min or longer at times.
Radio presets were gone, but other than that everything else worked fine. Not sure how the radio will react on your '02 though. What you may try (and I have before) is connect a portable "jump start" unit to the battery cables (behind the screw on the clamp) while changing the battery, so none of your presets will be affected. Be carefull not to cross the cables though....

 

Thanks all, correct diagnosis on the battery, ran jump leads from the wifes car and it is now at least trying to start.
However, it's still not igniting, I've looked through other threads and it sounds like it's suffering from the flooding problem that seems very common. I've been trying to turn the car over (throttle flat on the floor) intermittantly for about 1.5 hours now with no joy. Due to the charge in the battery I've not been able to do the 60 secs on 30 off, more like the other way around. I've now got the battery on charge to see if a bit more power will help.
Any more ideas, been really helpful so far?
Thanks

 

I would check for fuel and spark first.

 

We recently had a situation that the car would not start in “P” but did start in “N” give that a try first.

 

Gus, are you suggesting that the engine will crank via the starter in N and P, but only fire and run in N?

My interpretation was that the OP said, with a jumped battery, he could get the engine to crank, just not run.

 

Yes that is exactly what I am saying. And I confirmed it with him just moments ago. As strange as it may seem this is what he told me tonight.
https://www.jaguarforums.com/forum/s...t=34052&page=3

 

Reading the linked post, I don't see it that way - I just read that the engine will both crank and start in N, but neither crank nor start in P: "Stick in 'P', no start, 'engine failsafe mode'. Stick in 'N' started immediately and ran perfect"

Your statement about confirmation refutes this - implying the engine will crank in BOTH P and N but ONLY start and run in N?

This is so contrary to the norm, which is why I am asking for absolute confirmation.

 

Thanks Gus, I tried it in N but it was exactly the same. I've now taken the battery out and put it on a slow trickle charge to try and get it back to full health before trying anything else. Looking at a few other threads, a slightly unhealthy charge can cause a lot more problems on these machines than on most others. Any max period of time I should have it out of the car?

 

It was me that had the recent 'no start' problem and I confirm that in my case the car would crank in both P and N but only start in N. In P the cranking was accompanied by the warning signal "engine failsafe mode".

 

Norm is not the only answer when it comes to Jaguars!

 

I just had this issue with my 2001 XJ8. If the car is clicking and you're going into failsafe, it's unlikely that the battery is at fault. It sounds to me like a a sensor problem, probably a mass air flow sensor or one or both of the O2 sensors (or some combo of these sensors). You're gong to need to hook up to a scanner to get the codes on this one. The sensors are a relatively easy fix, particularly if its the MAF. The 02 sensors are pricey though around $250 each (MAF is around $150). You may also need an oil change, depending on how much fuel was pumped, but not burned on your start attempts.

Let us know what the mechanic says.

 

Absolutely! One of the reasons I love mine so much is because it sometimes provides a challenge to my technical abilities... Thank goodness I have other vehicles to use while I'm learning how to overcome the newest challenge - knock on wood, it hasn't shown up yet. And, thank goodness I have prior experience in CAN bus systems.

 

Thanks est, its not going into failsafe mode and with jump leads on it was cranking but not firing. I've topped up the fluid and I've had the battery on an optimiser for 3 days, charge is slowly improving. I've sniff tested the engine oil and I dont think its contaminated with fuel, as soon as it started turning without firing I stopped and started trying the foot to the floor method for dry starting. I'm hoping that with a healthy battery it might fire up.