I have a 2005 UK RHD Jaguar X-Type Sports Premium Estate 3.0 V6 Petrol with Manual gear change, which I have imported into Spain.

The car has a history of parasitic drain that eventually causes an issue with the 12V battery. To solve the problem, I had a battery disconnect (rotating) switch fitted to the 12V battery negative cable and also had the bonnet opening switch (which is located in the far corner of the engine compartment nearest the UK RHD passenger) disabled via a reversible (if I ever want to reconnect) cable connector. The 12V battery disconnect switch worked fine, allowing me to:

1. Release the bonnet
2. Lock the car with the key fob.
3. Open the bonnet fully (bonnet opening switch disabled, no alarm).
4. Disconnect the battery with the rotating switch.
5. Drop the bonnet and leave the car parked for a month or more.
6. No parasitic drain or other 12V battery issue.
7. Open driver’s door with key (not fob).
8. Release the bonnet.
9. Connect the battery with the rotating switch.
10. Start the car (plus set Radio Code and Window One-touch Opening).

However, I recently had a bonnet release cable issue and a flat battery, which meant that I could not open the bonnet to jump start the car, When I eventually got access to the engine compartment, I refitted the bonnet release cable and purchased a new 12V battery. Now when I use the previously successful procedure to disconnect the 12v battery with the rotating switch, the car immediately sounds an alarm, initially the full alarm and horn, then the quieter secondary sounder (backup alarm). So I have had to leave the new 12V battery connected and subject to parasitic drain until I can resolve the problem. Somehow, I need to be able to use 12V battery disconnect switch without setting off either main or secondary (backup) alarms.

Your advice and experience appreciated, including references to other threads in the forum.

Old battery - Yuasa YBX5000 Series YBX5110 12V 85Ah 800A.

New battery - Varta F17 80Ah 740A.

 

Interesting way to solve a parasitic drain issue...

Just a thought I had about that (I am a design engineer, who specialised into switches):
I would not have designed anything, where the complete battery-current runs thru a cut-off-switch.
Who sells this kind of rotating switch? A reputable manufacturer or is this a Chinese design?
I would have used a very powerful relay, made for such a purpose and I would control this relay via a standard switch, which could even be in the passenger compartment.
Is it possible to easily dismantle this rotating switch? If yes, do so and clean the contacts (probably with very fine sandpaper).

And I am not sure, what tis "reversible cable connector" is, which you are using...: You prevent any alarm triggered by opening the hood normally simply by disconnecting THAT connector in the corner.

You forgot to write, AT WHICH POINT EXACTLY during your procedure the alarm is being triggered - which might be important.

Did you disconnect anything (and forgot to re-connect) or damage any wires while you were installing the new mechanical release cable?

 

That is odd. I would guess the bonnet switch disabling connector simply came loose as a result of banging on the bonnet to get it open and the cable refitted. The only other explanation that makes sense to me is the dead battery for a long period of time put the security computer into a different, more primordial state and it needs updating. I don't like that answer but it doesn't seem too farfetched.

There is a post on the XJ forum that says there is a switch in the hood latch itself and lubricating the latch damages the switch. I assume you lubricated the latches so this hangs together if you had an XJ and not an X-Type.

https://www.jaguarforums.com/forum/x...ocation-33613/

 

I do understand that if the wrong kind of grease is able to "infiltrate" the ajar-switch that this could generate the issue that there is at times no contact, where there should be a contact...
However, the alarm on the X-Type bonnet (hood) is deactivated, if the connector is disconnected, which is the same as the switch not having a contact - apart from the fact that the ajar-switch's position is irrelevant with that connector being disconnected. Thus, damage to the ajar-switch can't explain the issue...

 

I would think a simple solution would be to plug in/hook up a battery minder or pulse charger, or operate the car more frequently?
Am curious as to how you gained access to the engine compartment after not being able to open the bonnet due to the bonnet release cable issue and a flat battery?

 

I boughr this on Amazon 3 months ago and it works for me. I had to buy some battery connectors and make a short cable. It comes with 2 remote control fobs.
Knoweasy Car Remote Battery Disconnect Switch - 12V 240A Automatic Power Shut Off Switch with Manual Control

 

Hi Peter! The post I found with TSB relating to the bonnet open switch was specific to the XJ of the same years, roughly, of our X-Types. The X350/356 models. In that case the switch was located at one of the hood latches which is why it was being exposed to grease. It seems odd not to commonise the bonnet open switch (doubly so in the FoMoCo years) so I'm surprised it is a different switch in a different location between XJ and X-Type. Or am I misunderstanding? Is there an ajar-switch in the bonnet/hood latch as well as a bonnet/hood open switch up on/near the strut tower?

 

Hi dh53 (you know that 53 is Herbie's number, Herbie the super-bug, the movies with the VW Beetle?),

I think I can answer your question:

> It seems odd not to commonise the bonnet open switch (doubly so in the FoMoCo years)...

The pedigree of the XJ and the X-Type (X400) differ:
The history of the XJ starts in 1968. You can even see the general similarity between a '68 XJ and a 2009 XJ. Hence, many initial "systems" would have been carried over from the previous models of XJ (so that's where the X350/X356 lineage comes from). The pedigree of the X400 has completely different roots:

The basic Ford-idea was to design a Jaguar for the "masses", a cheaper one. The complete X400-project was sourced out by Jaguar and "MSX-International" had been tasked to design it. I worked for MSX and I worked in the X400 design team. The idea was to base the X-Type on the Ford Mondeo CD132 platform and use as many part carry-over as possible. However, it turned out that that was not as easy, and to ensure that the result is a Jaguar (and not a Ford), many parts (including switches - even internally) could not be taken from the Ford.
As a result the X400 project was way more expensive as expected, but the result was a Jag! Sadly, the foul-mouthing press destroyed the X-Type with their lies and by doing so the dug the grave for Jaguar: Not only was the development way more expensive, the sales figures were also way lower as expected (thanks to the foul-mouthing press).

I am fairly sure that this killed Jaguar! Ford then had to sell Jaguar for "an apple and an egg" (that is a German expression) to Tata in 2009/2010, which defines - as far a I am concerned - the death of Jaguar. I have read articles with speculations that what Indian Tata did to Jaguar was revenge for the British colonisation of India. But apparently making Jaguars, which look like a VW Golf or a Nissan, including the abolition of quad-headlights, was apparently not bad enough and the masses unexpectedly were still buying Jags. Thus, Tata went now for the next stab in the back of Jaguar and designed a woke insult of the Jaguar-brand, for which there is no customer base and for which no-one will have the money to buy those Barbie-cars anyway...

So, that's why the X400 has a bonnet ajar switch far away from the latch (about 1m) near the LH shock absorber (that big rubber think poking up), which (apparently) the X350 has - according to what you are saying - the ajar switch incorporated in the opening latch (I can't confirm, as my X308 (which is probably similar in those regards), is - although fully functional - currently nicely wrapped up to be protected from the weather...