I am currently experiencing a battery drain on my car that after three days fully drains the battery. The electrics are not shutting down after the 40 minutes it takes the car to go into sleep mode. I know this because the four power relays in the boot are staying on and constantly warm. After reading some posts I suspected the rear electronic control module so I replaced it; however this has made no difference. I also removed the accessory relay from the fuse box in the cabin, still no difference. Has anyone had the same problem with the four power relays staying active, if yes what was the cause. I have also purchased a front electronic control unit; does this have anything to do with the rear power relays? Would it be a good idea to remove half the fuses from the boot fuse box to try and narrow down which possible component was causing the drain?

 

Car info?

 

Sorry, Jaguar S Type 2.5 2003 Automatic

 

Be careful not to remove any relays/fuses which could be (meant to be) involved in the multi-module shutdown (the one that's not happening!). (Not meaning you would do that, just raising it as an issue.)

 

I have not had time to properly diagnose, but I think we have the same issue - be it mine seams to be intermittent.
JagV8 - I don't know anything about the "multimode" shutdown, last I looked at the rear schematic 2months ago, it appeared that all 4 relays were basically in parallel.
Relays do fail with age, is it possible or likely, that one of these 4 relays in the trunk could be 'sticky' and causing an intermittent sleep mode? - for the low cost of 4 relays, I am just thinking now it might be worth a gamble, I dont' like gambling on "Modules" like two BECM's, but relays are inexpensive, a have moving / wear and tear parts????

Bouncing this idea around....

PEte

 

Hi Pete, After reading a post about the ignition switch sometimes being the cause of battery drain i decided to disconect the ignition switch. After waiting for 40 mins the four relays in the boot switched off (all cold). You can tell this by feeling if they are warm, if warm they are energised. So it looks like the problem on my car could be a worn ignition switch.

 

Excellent - sounds very promising!
Brutal's mentioned problems with that part before so you may like to check out his posts. Advanced Search can search for key words posted by a specific user.

Relays - could be worth a try. As you say, quite cheap. Brutal's pointer to the ign switch / mechanics etc is good, though.

 

THanks guys, as per form recommendations - I did the ignition switch back in January.
HOWEVR: I had the radio/AC control out on the floor all thru January during/after managing to change the elec portion of the switch. The battery held charge for 3 wks during all this.
I put the radio back in, drove for a day, then 2 days later - toast.
I have an aftermarket radio, however this problem I am certain has been present intermittently well before, and after installing the aftermarket radio (the rear amplifier remains stone cold off when I have checked it a few times).
I'll start monitoring the temp of the relays each morning and report if i see anything warm with them.
My troubleshooting is kind of haphazard to be really correct and effective, but I just have too much else on my plate these days, and its still pretty uncomfortable in the garage.
Pete

 

At last i've found the course of the battery drain, it is the climate control unit and not the ignition switch that I thought it was. I turned the climate control unit off then 40 minutes later the relays turned off. I know this for sure because I tested them by removing the relay and placing it back in again to see if it would click, no click. All I need to find out is why the climate control unit when switched to on stays on after the ignition is turned off. Any ideas.

 

Running Man;
I have suspected this but not investigated, thanks for the post.
One think I have noticed is that sometimes when I start the car in the morning all the defrost/mister/windsheild switches illuminate, sometimes not. At first I though if it was below a certain temp that this was automatic, I don't think so - I don't drive it regularily enough, but will watch this. Generally the A/C unit is left 'on' as far as the push button switch is concerned.
Did/do you notice anything similar?
Pete

 

I have the very same issue on my '03 ST 4.2L. All 4 switched system power relays are staying warm and draining a 14 mo. old battery. I'm not sure the exact cause yet, but could it be my RECM and SCP stored messages? How do you disconnect the ignition switch? is there a fuse or plug? Also is there a way to reset the RECM? would that clear any SCP messages? Trying to troubleshoot this frustrating issue.
Thanks

 

There should be SCP messages, up to the point there are no reasons left to keep sending them. Problem with key flap would cause more messages, for example. Of themselves SCP messages are not a problem. It's why they're being sent that matters. Usual causes are key flap, bad relay, bad wiring, damp/water in trunk (aka boot).

 

Don't think it's the ignition flap (as it does not seem to stick when slowly pulling key out), no water in boot or signs of water. Could be bad/faulty wiring. Could all 4 relays be bad, or would one be bad in series with all 4, causing all switched system power relays to stay warm (active)?

 

If I suspected any relay(s) I'd swap them for known good one(s)

 

One easy test for the ignition switch flap problem.

When you shut off the car and remove the key. Watch that the red emergency brake light goes on for a few seconds then goes off. This signals that the car knows the key was removed (flapper closed) and has applied the EPB.

If the car does not apply the EPB automatically then suspect the flap issue. Some lubrication might help too.
.
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Yes, I've done that with like relays that were cool to touch after car sat for several hours, and swapped with ones that were warm, and the known good ones felt warm after just a couple of hours.

 

Yes I observed that, and the EPB light stays on as it should, after removing the key from the ignition, then will go off after some seconds pass. So I know that it's not the ignition flap staying open.

Thank you

 

For what it's worth, here's a pic of what my battery looks like. Does the positive lead wire look ok?, it seems to be a few inches too long, and kinda crimped. Not sure this would cause the relays to stay active though.

 

Personally, I don't like Interstate batteries in my Jaguars.

To confirm - this battery does have the provision for the air vent (looks like it's hooked up)

Cable looks long but is not the cause of your drain issue.

 

Was there any luck resolving this issue?
i have exactly the same symptoms,
relays on after 40mins

have dropped around 15 hours into it so far