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When I turn off my Jaguar 98 Vanden plas brand new batteries are drained in a day or two days .could it be the alarm system somehow or what could be draining the battery so fast
From my understanding there are 3 things that will drain the battery other then trunk lights and other lights .
1 . One of the king relays in the corner of each fuse fuse box does not open as you rotate the key around to off , you can feel for them to click off as you rotate the key to off . Or they won't click as the power contact inside the relay is fused closed or the pulling coil inside the relay does not lose it's ground provided by key rotation .
2 . The key in key out switch does not provide the ground to start the shutdown sequence / go to sleep command the the Security module ( SLCU )so the car stays alive and not go to sleep .
3 . The steering column or seat retracting is stuck and doesn't send a agreement position sensor signal that they're retracted as you pull the key out telling the SLCU that it can start the start the shutdown sequence . You can remove this requirement the SLCU looks for by turning the large knob on the side of the steering column from auto to off .
Shall we play ?
Last edited by Lady Penelope; 04-11-2018 at 01:25 AM.
Could also be a failing relay stuck in the "on" position. Connect an ammeter in series at the battery and see how much current is flowing with the car off. Then start pulling fuses one at a time to isolate where the current drain is coming from.
Traci, I would first try a shot of WD-40 into the ignition switch with the key inserted half way. There is a small flap that gets gummed up and doesn't close completely. The little flap tells the SCLM that the key is removed from the ignition system and begins the shutdown sequence. If it sticks just slightly the car want go to sleep mode. and will cause a high battery drain.
The next thing is to make sure the FOB is actually locking all doors. That also effects the sleep mode.
By the way stop by the western area forum and add your name to the Las Vegas list. I will be trying to get the Vegas members together in the next couple of weeks.
Mine died after 3-5 days, until I got a smart battery tender. I've read that the alarm sounder/speaker is responsible, that when it's internal battery dies, it then continuously shorts out.
My alarm sounder failed in such a way that it started backfeeding power from its battery into the wiring and kept a couple of relays on in the engine compartment. One relay was running the SC pump and the other the Throttle Body, even with the ignition off. If you have a really high drain, check whether your TB is humming continuously after ignition switch off.
04-11-2018, 12:38 AM
