Headlight Failure Service Requird

[CTCNetwork]

Hi,

Or do an overnight trickle charge. Try to get 12+ hours of charging to get the battery up to near max charge.

Des. . .

[Semnoz]

Originally Posted by Moose Test

Just a thought but - could you not prove/disprove the low battery capacity theory by using a set of jump leads and a second/friend's/neighbour's vehicle, before you go to the expense of a new battery?

With the donors' alternator running and good battery tied into your power system that should be more than enough total instantaneous capacity, given that your's already has enough starting current available.

For whats it's worth, I ran my XC70 2008 D5 with an obviously degraded/failing battery for a couple of months and whilst I had poor starting performance and several 'low battery' warning messages, I didn't encounter any headlight issues.

Not sure that will absolutely prove it's a battery issue. If the donor car is running, there will be a continuous 14.4V from its battery, and cranking the V70 might only result in that voltage dropping to a value near to normal battery at rest. This higher and uninterrupted voltage might well prevent the headlamp issue, which could then rule out a mechanical fault, but doesn't answer the question of whether a good battery is OK on its own when cranking the engine.

I believe in some cars there are some electrical parts that take a feed directly from the alternator at start-up, to ensure they receive at least 12V during the engine cranking cycle....If the headlights are powered this way, I guess that could be a potential issue to investigate, but as there is evidence that replacing the battery fixes this issue, I'd say not.

[Moose Test]

Originally Posted by Semnoz

This higher and uninterrupted voltage might well prevent the headlamp issue, which could then rule out a mechanical fault

Quite the opposite. If the fault persists when there is a lower voltage drop and "good" battery (by merit of the donor) then it points to a wiring / control module / actuator problem in the headlight, not the battery. If the fault doesn't appear, then poor battery condition is a possible cause.

[Pidgeonpost]

Just been reading this thread as I've been getting this message occasionally on our car. Checking the headlights themselves they seem to be both working on dip and main beam. I've yet to drive the car in true darkness since we've had it, only in dusky conditions, and the headlights were pretty uninspiring, and the beams seemed rather low. I was reading elsewhere that the levelling of the headlights reverts to the low position if the headlamp control module goes on the blink.

Then last night I also got a 'BLIS function reduced' message (or something similar). This seems to have gone away today, but I've a feeling it may be back.

Reading elsewhere online it appears that either or both of these conditions can be caused by low battery voltage, and I must admit that in the last few weeks most of our trips have been only about 5 miles each way. I don't know the age of the battery, and I won't be having a look just yet as it's 33C out there.

Meanwhile if anyone has any clues on the above I'd be glad to hear. Thanks.

[ferg55]

Headlamp message more than likely battery - originals are good for 10 years or so, replacements less.

BLIS message usually caused by low sun, reflections, rain or road spray, or just a dirty camera lense. IIRC, its an image recognition based system (recognises car outlines in the day, headlamp patterns at night) so anything like that can confuse the system. Happens to mine regularly.

If you're on the original xenon bulbs, renew them. They deteriorate with useage and the output drops significantly. They are on all the time with Volvo's remember

[Pidgeonpost]

Originally Posted by ferg55

Headlamp message more than likely battery - originals are good for 10 years or so, replacements less.

BLIS message usually caused by low sun, reflections, rain or road spray, or just a dirty camera lense. IIRC, its an image recognition based system (recognises car outlines in the day, headlamp patterns at night) so anything like that can confuse the system. Happens to mine regularly.

If you're on the original xenon bulbs, renew them. They deteriorate with useage and the output drops significantly. They are on all the time with Volvo's remember

Thanks for this. Had a quick squint at the battery voltage last night, but only using the display on 12v USB phone charger adapter thingy. This showed 14.0v just with ignition on, and dropped to 12.8v when I started the engine. Whether that says anything significant I'm not sure, but it was too late to dig out the multimeter.

The battery is a Yuasa.

https://postimg.cc/r0fNkcVZ

There's often a stamp on one of the terminal posts to tell the year of manufacture, but there's nothing on this one. There's a code stamped on it, but I can't deduce the year from that.

https://postimg.cc/9zfBB4b6

The date may be present elsewhere on the battery, but I needed to use the car and didn't want to disconnect the battery to find out. The little green tell-tale is errr...green, which I naively believe is a good sign.

The headlights. Again, I'm going to show my ignorance as I don't know the type of headlight. They don't do any of the fancy manoeuvres that they did on our BMW or Skoda, and there's no rotary control for headlight adjustment shown in the handbook.

https://postimg.cc/GT9J3N9L

Are you able to determine the type from that perhaps?

I guess I'm going to have to take it out in true darkness to see how good or bad the beam pattern is.

Any help appreciated.

P.S. I cleaned the lenses on the BLIS cameras so we'll see how it goes.

[FreshAir]

Originally Posted by Pidgeonpost

Thanks for this. Had a quick squint at the battery voltage last night, but only using the display on 12v USB phone charger adapter thingy. This showed 14.0v just with ignition on, and dropped to 12.8v when I started the engine. Whether that says anything significant I'm not sure, but it was too late to dig out the multimeter.

The battery is a Yuasa.

https://postimg.cc/r0fNkcVZ

There's often a stamp on one of the terminal posts to tell the year of manufacture, but there's nothing on this one. There's a code stamped on it, but I can't deduce the year from that.

https://postimg.cc/9zfBB4b6

The date may be present elsewhere on the battery, but I needed to use the car and didn't want to disconnect the battery to find out. The little green tell-tale is errr...green, which I naively believe is a good sign.

The headlights. Again, I'm going to show my ignorance as I don't know the type of headlight. They don't do any of the fancy manoeuvres that they did on our BMW or Skoda, and there's no rotary control for headlight adjustment shown in the handbook.

https://postimg.cc/GT9J3N9L

Are you able to determine the type from that perhaps?

I guess I'm going to have to take it out in true darkness to see how good or bad the beam pattern is.

Any help appreciated.

P.S. I cleaned the lenses on the BLIS cameras so we'll see how it goes.

The green indicator does show the battery should be in good health. It looks like it is just a lead acid battery, not an enhanced flooded one but I could be wrong.

Best to measure voltage with meter or OBD reader. 14V when not running is not likely to be accurate. 12.8v would be good. 12.4v lower level of charge and best get the battery charged.

[Simmy]

try cleaning the contacts on the h/l leveling motor it only takes a small break in connection to log a fault try to get code read with vida as it also sugests possible causes this is why vida is best for volvos

[Pidgeonpost]

Originally Posted by Simmy

try cleaning the contacts on the h/l leveling motor it only takes a small break in connection to log a fault try to get code read with vida as it also sugests possible causes this is why vida is best for volvos

Thanks Simmy. I can check that (if I can find it). I don't have Vida, but I have run a scan for error codes using Car Scanner - nothing reported except the couple of glow plugs previously identified. Will keep digging...

[Simmy]

check the moveing parts for free movement you will need an assitant to operate the ignition or to watch the movement .