Low battery warning

[griston64]

Originally Posted by Tatsfield

It wouldn't have done damage, just by passed the monitoring system and blinded the ECU as to what was happening in the battery during charging. I did it before someone on the forum advised against bolting to the terminals.

I also did same when I first got my CTEK. I now have same set up as Tatsfield but my charger just sits on the garage floor.

[Peter2400]

What if you take out the battery to charge and connect the charger to the terminals? You cant charge it that way then?

[Tatsfield]

The connection requirement is related to the car not to the battery but why would you want to take the battery out if you can safely charge it in the car?

[aaronh21]

I had the same issue with a Volvo XC70 P3 D5 I've just purchase looking in the service history the previous owner spent about £700 trying to resolve the issue, new alternator and 2 new batteries. The problem with modern cars that have stop start is a new battery has to be recognised by the car,

To do this you need to pull the BMS sensor cable whilst the car is running. Leave the cable disconnected for about 30 seconds then reconnect, switch off the car and lock it and leave it for about an hour so all the systems power off and you shouldn't see the message again.

[FreshAir]

It is possible to initiate the procedure on the car without tools etc.

For a reset of the BMS:
1. Switch on ignition (do not start engine)
2. Switch on dipped beam
3. Press 6x the rear fog light button (this does not mean to switch 6x on and off the rear fog light)
4. Press 3x hazard lights button (do not switch 3x on and off hazard lights)
5. Then the battery symbol in the speedometer should flash 3x quickly.

Leave car parked overnight afterwards.

[Graham 2940]

Could be a lot of things apparently. I had it low battery warning, I did do the battery registration trick by disconnecting that little gadget that sits on top of the terminal for about 20 seconds then left the car over night

The message didn’t come back on, but a few days later my alternator belt snapped due to a seized alternator override pulley

New belt fitted - weeks later message has not come back

So was it the battery registration or had the belt stretched, maybe it was both.

Hope this helps

[yostumpy]

Originally Posted by FreshAir

It is possible to initiate the procedure on the car without tools etc.

For a reset of BMS
3. Press 6x the rear fog light button (this does not mean to switch 6x on and off the rear fog light)
4. Press 3x hazard lights button (do not switch 3x on and off hazard lights)


Leave car parked overnight afterwards.

Surely if you only press the hazards 3x , they will remain on?

[Tatsfield]

My assumption would be that once you initiate this code input procedure, the buttons no longer operate the circuits to which they are dedicated but perform a direct input function into the ECU, so it doesn't mean that the hazards come on and stay on as the button doesn't connect with them while the coding is taking place. The ECU will have a protocol that switches the functions of the requisite buttons once it receives the beginning of the code instructions. This is certainly how the system worked on my previous cars and I see no reason why Volvo wouldn't follow the same technical route.

[FreshAir]

Originally Posted by yostumpy

Surely if you only press the hazards 3x , they will remain on?

Yes, but once you see the icon flashing to indicate the procedure is initiated, you can turn off the hazard lights. I'll add it to my notes so they are included next time.

[apersson850]

Originally Posted by FreshAir

It is possible to initiate the procedure on the car without tools etc.

For a reset of the BMS:
1. Switch on ignition (do not start engine)
2. Switch on dipped beam
3. Press 6x the rear fog light button (this does not mean to switch 6x on and off the rear fog light)
4. Press 3x hazard lights button (do not switch 3x on and off hazard lights)
5. Then the battery symbol in the speedometer should flash 3x quickly.

Leave car parked overnight afterwards.

The battery symbol will only flash if you have a TFT dashboard. The sequence still works with the older versions of dashboards, but there's no indication of that it's completed. We have one of each, so I have tested this.