Hi,
I wondered if anyone knows what’s wrong with my S-Type R?

I am getting the following on the dash: engine light on, brake light on, engine systems fault, park brake fault, and DSC not available. The car then goes into limp mode.

It will run fine again if you turn the ignition off and then on again. The battery is brand new, so it isn’t the problem. Any help would be very welcome.

 

It sounds like a flat battery - did you fully charge it (say 10amps 12+hrs)?

Also, is it a hefty one (90Ah or more)?

Next, there could be a quiescent current drain - see threads about them.

 

It is definitely not the battery. The battery was charged overnight and is working fine.

 

Follow final item, then.

 

Get your supposedly good battery load tested. Bet you'll find the battery maybe holding voltage but failing under load.

 

Oh stop it, you're killing me! That's the funniest one I've heard all day. If you're going to tell jokes, so will I:

What did the Secret Service agent yell to the President after seeing a gunman nearby? "Donald, duck!"

(Pause for laughter to die down)

Okay, I'm obviously yanking your chain a little bit, and using cheap humor to make a point, but don't paint yourself into a corner when troubleshooting. There is absolutely no guarantee your new battery is good. Don't automatically rule it out just because it is new. I have burned myself that way more times than I care to admit. The battery itself isn't the most likely culprit for now, but do keep the possibility in the back of your mind.

If the battery itself isn't at fault, low prestart voltage (for reasons still unknown) is the most probable cause. Take a look here, and note the similarities:

https://www.jaguarforums.com/forum/s...attery-193787/


A little more background will help, too. When exactly do you get this slew of faults? Right after first start in the morning? Or does it happen while driving? Why was the battery replaced? Was it part of an attempt to fix these faults, or was it changed for other reasons and then things started acting up? Ginger or MaryAnne?

You mentioned you can clear the faults by shutting off the engine and doing an immediate restart. That strongly suggests low prestart voltage was behind all this. If the voltage was a little low on the first start (several possible causes, not just the battery itself), the alternator would add a little juice and then the prestart voltage might be just above the magic limit for the restart. Voila! The faults magically clear.

Here's how I recommend to proceed:

1) First thing in the morning, check the prestart voltage. Unlock the car and open the trunk. Measure directly on the battery terminals. You should see at least 12.6 volts. This is a VERY high standard. From forum experience (see the link above), this is the magic number you need to see before starting, or the various computers will not be happy. Why is everything so finicky? Heck if I know, that's just how it is. Don't skip this important step, telling yourself that the starter speed is normal, so the voltage must be good. It doesn't work that way.

2) Check your charging system. Measure voltage at the battery terminals again. On a 2003+ model, you should approximately 14.5 volts right after start, settling down around 13.5 volts after a few minutes.

3) Hook up a battery charger overnight, for several days in a row. You'll want an automatic charger with at least a 10 amp output. Don't waste your time with a trickle charger. With the battery fully charged like this, see if the faults return. Most likely they will not. Repeat this for several days in a row. Yeah, I know it's a pain, but it doesn't cost anything except your time, and will provide some very good troubleshooting info. If all is good each morning with a fully charged battery, then you know low prestart voltage was the problem. The next step will be to determine exactly why.

4) Run a quiescent drain test:

https://www.jaguarforums.com/forum/s...-drain-123535/


If all of the above pass, your new battery isn't cutting the mustard.

 

Any updates?

 

Why does no one update? I am now having the same issue. Just got car back from repair shop and had the ECU relay replaced. On the way home, after wide open throttle the car was stuck had not power and no response to the throttle. I coasted to the side of the highway with all the warning codes lit up. Tried restarting a few times to no avail. Then, after a few minutes, it restarts and drives fine. The car ran great for several days but then had the same thing happen again.

Judging from this and similar posts, its a common problem and probably not too expensive to fix but nobody closes out the posts with how it was resolved!

 

My car is currently in the workshop, where it has been for four weeks. Mechanic is investigating an electrical problem.