Hello All,
Here’s a strange question:
I had been having the “Reduced Performance” warning on the little readout on the dash every time I started my 2004 STR. But it would go away after a minute or two, never to be seen again until the next engine start up.
Had the power steering pump replaced and got the car back yesterday. (Also fresh coolant on the same service.). Have driven the car 5 times since getting it back…No RP messages at all!!!
Could an issue with the steering system possibly have triggered the RP messages???
And the throttle response is noticeably improved.
Makes no sense to me…But this IS a Jaguar…So common sense usually doesn’t apply 😂!
Thanks in Advance
STR.Gringo

 

Not likely, but some component may have been removed and replaced fixing your underlying issue in the process. Have you ever run a scan for codes on the car?

 

As I’m over 100 miles from the nearest Jaguar servicer, I’m working with a local independent shop. I know they didn’t repair/replace anything else during this service. They have a very rudimentary scan tool. I’ll ask what codes they got.
Thanks for the help 😊

 

Any idea if the shop disconnected the battery during the repair? If so, that resets some learned parameters back to the factory defaults. Fuel trims are one good example. After a few drive cycles, the computer may make the same adjustments as before and the previous condition may reoccur.

Don’t panic if that happens. Get the codes, post them here, and we can go with that.

Make sure to ask for the 5 digit code (such as P0171), and not necessarily the definition given by the scanner. Sometimes those generic definitions are not accurate in Jaguar’s world.

 

Great advice! Thanks very much for the Heads Up. If “Restricted Performance” returns, I’ll get the code(s) and post them here 👍.

 

A word to the wise, Gringo: If you own an S-type (of any flavor), a code reader that can read both OBD-ii powertrain codes and Jaguar's proprietary chassis codes will pay for itself in short order. Mine did.

If your preferred shop only has a "rudimentary" scan tool, then that is twice the justification for you to have a decent one that is fit to purpose. (Unless you like walking, that is...)

 

In addition to the codes, use a voltmeter to check the available voltage across the battery terminals with the ignition in the OFF position for at least 30 minutes. If there's less than12.6 volts available, charge the battery at 2 to 5 amps for five hours and retest. If the voltmeter still indicates less than 12.6 volts, the battery must be replaced.

Many random instrument cluster and DTCs are the result of low available voltage.

 

Right 👍! I’ve already learned that Jaguars are particularly sensitive to battery voltage. Many on the Forums have mentioned this. But thank you very much for the SPECIFICS of what to look for, and how 😊! This will be invaluable for me going forward 😎.
STR.Gringo