1998 v70r battery drain sometimes

Janpy · Post by **Janpy** » 25 Sep 2022, 03:10

Goodmorning
Im Jan, living in the netherlands and owning a V70R , before a 850R.
And i have a strange thing going on in my car
Now and then my battery drains.
I did some research, and it seems relay 2/32 stays on.
When i pull fuse 11b/1 it shuts off
Replace the fuse it stays of.
This relais is switched by the ecu pin 41 -12v.
When i remove the ecu there no -12 on the relay
So no leeking 12v.
Also the ignition 12v to the ecu is switching normal.
Has ony one had experience with this.
Or am i on the wrong path and is relay 2/32
Always on for a while after switching of the igintion key?

Thanks
Jan

Post by **Goupil** » 25 Sep 2022, 04:31

That's weird, there isnt much in that circuit that could go wrong other than the ECU.

I've never heard a fuel pump staying on after switching the ignition off on, on the FWD p80 at least.
Is your V70R fwd or awd ? I dont know how the dual pump setup of the AWD works

Post by **abscate** » 25 Sep 2022, 05:03

It sounds like relay 2/32 is sticking closed. You might be able to swap it with another similar one for testing

It should be open with the key off

Post by **MrAl** » 25 Sep 2022, 08:21

Hi,

Relays that stick closed are somewhat common. Relays usually have to be overrated in order to last a very very long time. With DC current there is nothing to break the arc except distance between contacts so it's a little worse than with AC where the current goes through zero. The current goes thought zero 120 times a second in the US and 100 times a second in Europe so the arc has good reason to stop. There also has to be some contact wiping before they break so that makes things a little worse too.
Sometimes a snubber circuit is used to help kill the arc but not sure if they do that on automobiles or not.
My neighbor had a relay stick in their clothes dryer. Had to call the repair guy out.

Post by **abscate** » 25 Sep 2022, 08:44

You can see e snubber diode in 2/35 above. The three relays under the kidney fuse box in the engine compartment are all the same on v70s, so you can swap them to test. Pull and confirm first, please

Janpy · Post by **Janpy** » 25 Sep 2022, 09:31

: 20220925_175450.jpg (386.93 KiB) Viewed 275 times

Thanks for the reply
When i pull the the relay it switched of directly.
I believe i am on the wrong path.
When i check after a half hour the relay is off.
So it stays on for a while after switching off the ignition.
I have a fwd car, manual gear.

Jan

Janpy · Post by **Janpy** » 25 Sep 2022, 10:48

Me again
The picture is wrong, pins on the contact instead of the coil.
But i found out this relay shuts down after
5-8 minutes, so cannot cause this problem.
I keep on searching

Jan