Having owned several Jaguars I expect gremilns and their little quirks. And I have come to expect the same out of my latest toy. Anyway, my newest gremlin or quirk happened yesterday. I went to start it and had the cough thing again. It did this several times and finally started. As I was leaving, I noticed that the steering wheel was very heavy. Like I had no power steering at all. I had no other indications because I thought it might have thrown the belt off. I drove a mile or so and no change. I stopped, checked fluid and everything was fine including belt. Started it back up and now had power steering again. Anyone else experienced this?

 

Just took a look at the general description of the system in a service manual and only two things stand out. One is reference to the fluids being contaminated and blocking proper function. Recommendation is to flush the system.

The other references a "Steering Transducer" failure. Not sure yet where that component comes into play in our cars, but Ill try to look into it more if I can get the time. Maybe one of our Jag techs here can tell us more about it?

Few other possibility I see as well... not sure how to be helpful in diagnosing them
Faulty rotary valve/seal
Seized or worn steering gear


BOL
Vince

 

Have had the same here. Will report it to my dealer next week since my car is under Select Edition warranty.

 

Yes I have experienced this.
A couple of times when I have started the engine cold and stalled it by selecting drive too soon, restarted without a pause and driven off---steering heavy. On next restart steering back to normal.
I assume this is just a software effect.
Have experienced door locking failure associated with window and wingmirror failure which firstly cured itself after a while then more recently was cured by disconnecting battery negative for a minute or so.
However it did not cure the climate system fault which has also arisen.
No control of fan speed they just run around full power, temperature control works just very noisy full power fan(s).
Only respite is to turn climate off for a bit.
I have visually checked most of the fuses near passenger left knee.
Is it possible to obtain an electrical circuit diagram to help isolate and fix these electrical gremlins?
Fuse list in manual omits climate fans as far as I can see!
Julian

 

Sorry forgot to show model and revised signature.
Requesting circuit diagram information for XK 2006.
Julian

 

A very useful website www.justanswer.com provided the necessary help.
Located blower speed control module under passenger glove compartment area, remove soft trim under fan unit, plastic clips roll off fairly easily.
Module is secured to blower by two small Phillips screws.
Module approx 3inch by 2inch.
Voltmeter on blue wire should vary with different selected fan speeds.
(Voltmeter from blue to chassis)
There are four wires two thick two thin the blue one is one of the thin ones.
If voltage varies and fan speed does not then probably a dud module, remove for further test or replacement as choice.
Module is grey with huge heatsink fins in air duct, marked Denso 077800-0901 made in Japan.
Mosfet in unit a Toshiba K2313 pretty much dead short on all terminals, shown as obsolete item on digikey website, have ordered a mosfet IRLB3036PbF (£7.50 for two inc postage from rs components) which appears to have compatible characteristics of logic level drive although I have not put a scope on it to see if this is necessary.

 

new transistor (mosfet) works fine.