My 2000 Jag S type also keeps saying failsafe mode?

Either have a fuel pump going bad, or a high current draw due to corrosion of the wiring harness. Professional Diagnosis is recomended to prevent hours of swearing befor you realize the kids an hear you.

Your transmission is going into limp mode because of a fault. Get the tranny diagnosed.

Hi there:
They say 3.0L but really is for a 4.0L diagram location... CHECK HERE

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take it to jaguar and have the software checked and any fault codes removed ,

press the mode button continuasly until the clock flashes then put 12h or 24hr then type in the time

Its the key

Many things can cause this message, get it to a good jarage and have the fault codes read - this will tell you what is going on. Don't panic - it could just be a faulty sensor .. these cars are very prone to this. Try to avoid using a jag main dealer for the code readings as they are expensive and tend to ''overcompensate'' for repairs! Most good independant garages have the ability to read the fault codes.
Hope this helps - please post the fault when know.

I've got a 2000 that did the same thing. Get this, it was caused by a defective trunk seal that let water in my trunk and got my wiring wet. Could'nt even shut off the car, only way to kill it was to pull the positve battery cable, negative won't kill it. After all dried out, and jag dealer reset my failsafe mode all good....... until now i have a .500 ma draw on power while sitting unused, brand new batteries down in 1 week??

change diesel filter ok now

fail safe mode is something the vehicle computor will go into when there is a problem with the vehicle it allows u to get off the highway or road safely you need to take vehicle to repair shop or your dealer which ever u prefer Failsafe engine mode on a 2000 jaguar s type is caused by a stopped up throttle body. Jaguar says not to clean the throttle body since it has a protective coating to help keep deposits from accumulating. You can clean the throttle body as long as you use ONLY throttle body cleaner that states it is safe to use with a protective coating. The butterfly valve in the throttle body will actually stick not allowing air to flow into the manifold causing failsafe engine mode to kick in reducing the amount of power your engine will produce. To solve the issue just clean out your throttle body, it will cost you around $5 dollars and take 1 hour of your time.

This is from wikipedia.