V50 New battery yesterday. Flat today.

[HenriZ]

Originally Posted by ele288

You are confusing electric heater which was an option as well as fuel heater was. This is electric heater support as used in Ford focus even Ford part nr is stamped on it. In colder climates it was a standard with diesel engine as it takes long to get warm air in to the cabin. They do fail and are draining battery, replacing fuse won't do anything, just replace the heater or remove the fuse to fix the issue.

I am not confusing anything. The heater in question is a heater which can warm up the interiour before the engine is started. Our car does not have it.

In any case, I measured current draws over all fuses, including this one. No issues there.

I logged the battery (I have a datalogger) and it appears the 2,5A draw only lasts a few minutes after the key is removed. After that it drops to 0 - 0,01A.

So my preliminary conclusion is that this battery is simply dead. It's a 2011 V50, so the battery is now 11 year old. As I understood it, these Volvo's didn't get the best of battery's.

Ordered a Varta Silver battery to replace it, and also a replacement for the start-stop battery.

I expect it to be fixed then. If not, I'll be back.

The reason I think the battery itself is near death: today it was fully charged (came of the charger) and less than 20 minutes later (of which we were driving 10 minutes), it would not start.

Normally these batteries have about 90Ah. To empty that in like 5 minutes of not running not charging, it would need to draw impossible currents.

[Simmy]

i cannot understand why you are trying to resolve things with an 11 year old battery. most batteries only last 6/7 years . good move ordering a new one hope this resolves your problem .

[ele288]

I was chasing this problem for 3 months, did put a new varta 900 and this could kill the battery in 4 hrs. The electric support for the heater matrix has a short and you can either replace the heater or remove the fuse. Volvo had at least 4 different heaters as options, one was webasto (fuel driven, rare in UK), second was the electric block heater with optional fan heater on passanger footwel (mostly Scandinavia) and the electric support for heater matrix for Northern Europe is what we have in diesels in UK, you won't find this heater in southern cars (Italy, Spain). That's why you have the fuse in your fuse box. You can ask any volvo dealer with your reg for car configuration or just run vida and it will show that your car has the heater

[HenriZ]

I have no doubt the heater was the issue in your case. That doesnt mean that it is for everyone.

The new battery has been placed and so far the issue has been solved.

[rowdy]

Well my new battery drained overnight, replaced it with a better new battery and that drained overnight. Disconnected the 80a fuse and it’s been fine since.

No doubt it was your battery that was the culprit though, if it hasn’t drained overnight again. Hopefully that is your problem solved.

[HenriZ]

Originally Posted by rowdy

Hopefully that is your problem solved.

It is. It's now starting happily, and still doing so after a week. Also replaced the start/stop battery and reset the BMS, and now start/stop is functioning again.

I would like to speak to the Volvo engineer who placed the start/stop battery behind the front bumper. What a bumhole.