There was no response on my 01 S-Type this morning. Dead. I put the key in and tried starting, and nothing happened. Nothing on the dashboard; using the boot button did not open the boot. I had to use the key. The petrol cap switch under the dash will not open the petrol flap. No horn either. For the past few days, the interior lights will not turn off while I drive, so I took out the fuse. I did not use the car the past two days because it was raining, so rain can be ruled out. Other than that, the car was fine. Any ideas before I call the emergency auto service? Thank you,

 

The battery went flat. The roadside assistance people tested the battery, and there was no charge. Completely flat. They jump-started it, and all was fine. I drove it for 20-30 min and turned it off and back on, and it was fine. Why did it go flat? I can only think of the climate control not being completely off, even when the engine is off. Or there is a short somewhere that keeps the interior lights on while I drive. I took out the fuse for the interior lights. What could the issue/s be? Will get the battery re-charged tomorrow and get new F29, F30 and F33 fuses.

 

If your battery went totally "flat" there is a good chance that its days are numbered. Few come back adequately after being pretty much totally discharged.

You are going to have to test to determine the source of what appears to be a parasitic drain in the electrical system. The interior lights staying on is a significant starting point in tracing the root cause of the problem.

 

Look for posts on

quiescent current

 

After replacing the battery, check for voltage between the ground lead and ground with the lead disconnected. If there is voltage you are getting a drain on your battery and you should disconnect it whenever the car is sitting and not being used. Try pulling fuses to see if you can stop the drain. If a fuse removal stops the drain you can then focus on that circuit as the culprit.

 

thank you all, I will do as you say

 

There's a specific procedure you have to follow. When the car is initially shut down, some modules remain powered for about 30 minutes or so. You have to wait for them to enter sleep mode before testing, or you may mistakenly condemn good modules. You also have to be careful not to wake them up by opening doors, etc. Details here, see the PDF in post #1:

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

 

Should it be noted that to do this test the boot (trunk) must be open? This would turn on the boot (trunk) light, creating an electrical drain. I think removing the bulb from the light would stop this drain. No doubt one of the more experienced Jag specialists on here will correct me if I’m wrong.
In fact, I recall a problem I came across years ago where a battery kept going flat. The customer had installed a new battery and new alternator. Still the battery would go flat if left for 24hrs. Eventually, traced the fault to the boot light switch by locking me inside the boot. Sure enough, the light didn’t turn off when it was supposed to. The switch had been damaged.

 

Not sure removing the bulb would do the trick. I think if the switch thinks the trunk is open, the module will try to turn on the nonexistant bulb and won't go into sleep mode. It may eventually time out and turn off the light, but I'm not positive.

Instead, I'd suggest making sure the trunk switch operates correctly by observing the warning message (Same switch controls the message and light). If you really want to see the light, rather than lock yourself (or a helper) in the trunk, fold forward one of the rear seatbacks. Then you could see into the trunk without having to crawl inside. Might need to leave the windows down for better visibility. After confirming the switch operates normally, you could tape the switch in the closed position, leave the trunk open, and the module would think it is closed.

 

Prior to beginning any electrical circuit tracing, or diagnosis for a quiescent or parasitic drain, have the battery tested under load.

There needs to be a minimum of 12.6 volts present across the battery terminals with the ignition OFF when checked with a voltmeter. When the battery was fully discharged, did anyone check to see what voltage was present?

 

Just had second thoughts about testing the light inside the trunk. The control module (RECM?) has one input from the switch, but two corresponding outputs: The light and the message.

I suppose in a rare failure mode of the module, one output for the message may turn on/off properly, but the second output for the light could remain on. Therefore, it's advisable to confirm proper operation of both the message and the light.

 

Hi Roberto, I saw you new thread only now, The symptoms were obvious, it was obvious that if nothing works, the battery (or BATTEWY (Monty Python)) is dead.
I just flew through all the comments above...
If you want to determine the quiescent current, you obviously cannot measure the voltage between ground cable and battery minus, but you have to set you multimeter to DC current and plug the cable from voltage to current (and do not forget to put it back to voltage, when you have finished measuring your currents, or you will kill your multimeter the next time you try to measure voltage with the cable plugged into current). So, either disconnect the cable from either battery plus or battery minus, and "connect" this "disconnected" cable via those 2 wires from the multimeter and observe the current that is flowing for quite a while (one comment above suggests 1/2 hour. While doing so, "simulate" that the car is locked with everything switched off. Obviously you need to get access to the boot (where the battery is), and you don't want that light to be on. There are easier ways look at that light: Don't close the trunk, but simply make the Jag think, that the trunk is closed - and not by taping the "switch" down, because there is no switch, which can be switched down: The switch is integrated in the trunk locking mechanism: I just walked out to my Jag and checked it out: Open the boot and use e.g. your key to close the latch of the locking mechanism. This makes the Jag think the boot (trunk) is locked. Get a CTEK battery charger. I need even 2 for all my cars and they are in permanent use, whenever the sun shines (and power is free from the sun). When you finished charging, measure the voltage and measure it again on a day later.
After measuring the current (or while with a second multimeter) measure the voltage and multiply it with the current (in Ampere). Obviously, U x I = P (voltage times current equals Power (units: V x A = W)).
And if your quiescent power drain is acceptable, and your battery is flat after a short time, you know that your battery kicked the bucket...

PS: don't forget to "open" the open trunk (i.e. via remote or lock before you slam it shut again, i,e, open that latch again to avoid damage when you try to close a closed boot-lid...

 

Thank you Karl, Sporton, Peter and NBCat. I got a new battery. The old one went flat twice in 4 months, so I decided to get a new one. One variable is gone, I hope. The interior lights are still on when driving. I need to get new F29, 20, 33 fuses. if replacing them with new ones fails, I need to start tracing.

 

Duly noted. On my '02, the switch is a separate unit in the trunk lid to the right of the latch, with a plunger sticking down. This switch does not monitor the latching mechanism at all, only that the trunk lid is in the down position.

This is not to be construed as me being (W word). I was merely less correct than usual.

 

I meant to pick up on that one last time already, but forgot: What's your beef with F20, F29, F33? And of which fuses are you thinking? Engine compartment, passenger compartment or boot compartment. Well, if you have a 2001 and Karl's 2002 has a separate boot lid switch, you probably have that too.

Kudos on the new battery. I really recommend permanent daily measurement of the voltage now, to confirm that you do not have any excessive quiescent curenet (going down the drain). Else, you would have to buy another battery soon.

Generally Jags' power consumption and "ask" of the battery is huge. Which is why i do my best to assist. The S-Types were build when LEDs were not really as developed as today. I always throw out all filament bulbs of the interior illumination and replace them with LEDs. Word of warning: Unbelievably removing and more so the re-installation of the main dome lamp unit in the S-Type can be one of the most difficult things and drive you mad. And as the D says in LED: They are diodes: Normally they work only, if inserted correctly (plus/minus orientation), but at least they don't get damaged, if if have it wrong the first time. The more expensive LEDs have an inbuild electronic, making the orientation irrelevant.

And get a CTEK battery charger, if you are not a near-daily driver.