SEC500 Battery keeps draining

[MrsK]

Hi all

I'm at an absolute loss and being about as mechanically minded as a chocolate bar, I have no idea where to start!

My SEC500 keeps draining the battery overnight. It jump starts first time with no issues.

I've checked and I can't see any lights or buttons being on.

I thought I'd check if anything runs while switched off, such as cat seats and windows, nothing. But strangely enough, when the drivers door is open, the car seats and windows move without the keys being anywhere near it!

Any help or advice would be greatly appreciated.

 

[C16RKC]

The cars seats moving might not be a fault, and might be a red herring; it could be they activate so a driver can adjust before getting in, just in case the seat is too far forward.

But it sounds like you have a battery drain, or a bad battery. Your local Halfords will probably test the battery for you.

But after, and assuming the battery is OK, then you'd need to use a multimeter to measure the current at each fuse, and find the source of the drain. I have never done this myself, as I tend to cower out and let the garage do it.

 

[MrsK]

The cars seats moving might not be a fault, and might be a red herring; it could be they activate so a driver can adjust before getting in, just in case the seat is too far forward.

But it sounds like you have a battery drain, or a bad battery. Your local Halfords will probably test the battery for you.

But after, and assuming the battery is OK, then you'd need to use a multimeter to measure the current at each fuse, and find the source of the drain. I have never done this myself, as I tend to cower out and let the garage do it.

Thank you so much for replying.

I think I'll do the same. I wouldn't have any earthly idea and knowing me I'd muck things up more!

Off to the local garage she will go

 

[Blobcat]

I’d get the alternator tested by an auto-electrician- the diodes in the regulator pack can fail leading to a random fast discharge - it depends which diode is in circuit when the engine is turned off.

 

[C16RKC]

By the way, that is a stunning car!!

 

[MrsK]

I’d get the alternator tested by an auto-electrician- the diodes in the regulator pack can fail leading to a random fast discharge - it depends which diode is in circuit when the engine is turned off.

Thank you ever so much. I'm ringing the garage now to get it sorted

 

[MrsK]

By the way, that is a stunning car!!

Thank you

 

[EmilysDad]

.... Your local Halfords will probably test the battery for you.

....

Not sure I'd let Halfords do it .... I'm sure there must be a proper auto spark local to MrsK

maybe we could 'fix it together' with Diagnose Dan

Seems to be a very similar problem though the fix could be anything.

 

[Botus]

damp under the carpets keeping something awake is my vote - NICE video

 

[alexanderfoti]

The seats moving with the door open is normal, as this is activated by the comfort relay. Lots of MB's have this around this era.

If you measure the amount of current being drawn, it will give an idea of potentially what is draining it.

 

[MrsK]

Just a quick update. She will be going to the garage this afternoon

They will test the battery, alternator and if it is neither of those, they will be going more in depth.

I've also bought a portable jump starter... just in case

I'll keep you all updated. Thank you all for your help and advice.

 

[Slartibardfast1]

Just a quick update. She will be going to the garage this afternoon

They will test the battery, alternator and if it is neither of those, they will be going more in depth.

I've also bought a portable jump starter... just in case

I'll keep you all updated. Thank you all for your help and advice.

We need to see a pic of your car please

 

[C16RKC]

That's never turned down! Especially a beautiful SEC like that

 

[MrsK]

That's never turned down! Especially a beautiful SEC like that

I'll take some pictures of what she looks like now, but she isn't quite as clean as my profile picture

 

[C16RKC]

We'll use our imagination

 

[MrsK]

We'll use our imagination

You'll definitely need it!

 

[AndySlade]

I’ve heard @C16RKC has a lurid imagination!