Car Lights - dim

[Diver Fred]

I hope someone can give me some guidance, please.

Vehicle :- Honda Civic Tourer 2017. Petrol / Auto

Problem :- the Driving (Head) lights are not bright enough to drive with especially on Dip beam - in fact I've taken to using the Fog lights to supplement the permanently On dip beam. Last night driving along the A14 the lights seamed to dull, yellow/orange without much range.
Of the A road using main beam the road illumination was a little better but still not what I say 100%.

Bulbs are H7 55w Halogen.

The headlight reflectors (Main beam) and Lens (Dip Beam) are clean and shiny and no signs of moisture inside the light assembly.
Headlight levelling system is set high but does definitely work.

Spoke with the dealers who I bought the car from and who service it. Their suggestion was check the bulbs for cleanliness and signs of clouding on the inside of the bulb envelop.
Well that 2 hours to get to Offside bulb and check it to find it is clean internally and externally. It took another 2 hours to get it and the other bits that had to come off to get it back (you really need a 5 year old to get their hands into the back of light assembly to get to the bulb!).

Checked voltages (with a 10MΩ voltmeter as follows :-
at Battery terminals engine Off 12.6v on 'Hot' side of headlight bulbs with lights on 11.5v
at Battery terminals engine On, fast idle (1500 RPM) 14.4v. on 'Hot' side of headlight bulbs with lights on 13.5v

There are relays in the power to headlights circuit.

Does that volt drop at the headlight bulb seam right?

Thoughts? Where to investigate further?

Edit:- Changed Title to bump question up the list.

 

[norseman]

I have precisely the same problem with my 26 year old BMW & like you use the fogs as well as dipped beams, though there is no suggestion of any other problems with the light units.

I've got some uprated H4B bulbs on order & my local garage will be tasked with fitting the damn things as I have arthritic fingers & little/if any patience. I'll post as to any improvement in light output.

 

[carmanmemoranda]

I hope someone can give me some guidance, please.

Vehicle :- Honda Civic Tourer 2017. Petrol / Auto

Problem :- the Driving (Head) lights are not bright enough to drive with especially on Dip beam - in fact I've taken to using the Fog lights to supplement the permanently On dip beam. Last night driving along the A14 the lights seamed to dull, yellow/orange without much range.
Of the A road using main beam the road illumination was a little better but still not what I say 100%.

Bulbs are H7 55w Halogen.

The headlight reflectors (Main beam) and Lens (Dip Beam) are clean and shiny and no signs of moisture inside the light assembly.
Headlight levelling system is set high but does definitely work.

Spoke with the dealers who I bought the car from and who service it. Their suggestion was check the bulbs for cleanliness and signs of clouding on the inside of the bulb envelop.
Well that 2 hours to get to Offside bulb and check it to find it is clean internally and externally. It took another 2 hours to get it and the other bits that had to come off to get it back (you really need a 5 year old to get their hands into the back of light assembly to get to the bulb!).

Checked voltages (with a 10MΩ voltmeter as follows :-
at Battery terminals engine Off 12.6v on 'Hot' side of headlight bulbs 11.5v
at Battery terminals engine On, fast idle (1500 RPM) 14.4v. on 'Hot' side of headlight bulbs 13.5v

There are relays in the power to headlights circuit.

Does that volt drop at the headlight bulb seam right?

Thoughts? Where to investigate further?

New bulbs regardless, possibly "uprated" versions, but keep to 55w.

Its such a pain getting bulbs out it's pointless putting old ones back in.

May not cure it and you need to look a bit deeper, but chances are it's old bulbs just tired

 

[Belle427]

Bulbs degrade so i would guess some new ones would help, id go for osram nightbreakers personally but you may find people will start flashing you as they think your high beams are on!

 

[JohnD]

Is the headlamp "glass" cloudy?

Are your eyes nearing retirement age?

 

[Old Salt]

Make sure all the connections and earths are clean as well to minimise any loss of power.

 

[robinbanks]

Do the bulbs get any brighter if you wire them directly to the battery? If wired direct to battery don't get 14v at the bulb?

Do you have a mate who would be willing to drive another car (with similar lights, no xenons etc) to some dark lane, two cars pointing away from each other on dipped beam so you can check it's not your eyes/psychological (does your mate think they're bright enough to drive by? Do your lights throw a similar beam pattern to his?)

Many times I've seen things like bulbs fitted upside down/wonky or the headlight angles misadjusted that basically means there's this crazy bright spot on the floor about 10 feet in front of the car then nothing

 

[JohnD]

In the old days, people used to check and adjust their headlamp alignment by shining them on a wall in a dark area.

Might be worth a try.

 

[robinbanks]

In the old days, people perhaps took the time to learn and fix their own stuff.

Now they know nothing and take it to Halfords so some failed GCSE work experience kid can make a hatchet job of fitting new bulbs..

 

[Rodders53]

Bulbs degrade so i would guess some new ones would help

Not modern headlamp bulbs like the OP's H7 halogens.
Tungsten halogen lamps are designed not to... the halogen scours the evaporated filament metal (that causes blackening) off the quartz glass wall and redeposits back onto the filament. Eventually the filament thins at one place on the coil and then fails (on switch on from cold surge usually).

Bulbs are H7 55w Halogen.

12 V and 55 W = 4.6 A
4.6 squared (21) x lamp resistance = 55 so R = 2.62 ohms
* when hot: it'll be a lot lower and have a higher inrush current from cold

Checked voltages (with a 10 MΩ voltmeter as follows :-
at Battery terminals engine Off 12.6 V on 'Hot' side of headlight bulbs with lights on 11.5 V
at Battery terminals engine On, fast idle (1500 RPM) 14.4 V on 'Hot' side of headlight bulbs with lights on 13.5 V

Volt drop engine off or engine on of 0.9 V = identical.

IF the current doesn't change from the 4.6 nominal 12V, at the higher operating voltages, that gives a wiring loom / switch relay resistance of around 0.2 ohms. Much thicker cables installed might halve that, but is it worth it? Ensure there's a good solid 'earth' return connection to the vehicle bodywork?

Note that the higher the volts on the filament, the hotter and brighter it will burn and the shorter its life will be. The makers know this to make 'brighter' and 'whiter' lamps by tweaking the filament design ratings ...

See the table in this Bosch H7 lamp range --

https://www.amazon.co.uk/Bosch-H7-Plus-200-Gigalight/dp/B0C3HVTPRS/

1150 hours for standard. 250-400 hours for the brighter ones. I note that the lumens output also doesn't match the 150 or 200% brighter claims.

 

[carmanmemoranda]

Not modern headlamp bulbs like the OP's H7 halogens.
Tungsten halogen lamps are designed not to... the halogen scours the evaporated filament metal (that causes blackening) off the quartz glass wall and redeposits back onto the filament. Eventually the filament thins at one place on the coil and then fails

Experience says just replacing old bulbs with new ones (of the same type) usually makes a noticeable difference. Often noticed if just replacing 1 side

 

[Rodders53]

Experience says just replacing old bulbs with new ones (of the same type) usually makes a noticeable difference. Often noticed if just replacing 1 side

Tungsten bulbs or tungsten halogen?
The former blacken inside with age, and that reduces light output.

 

[carmanmemoranda]

Tungsten bulbs or tungsten halogen?
The former blacken inside with age, and that reduces light output.

Halogen, h4 and h7 types

 

[Diver Fred]

Make sure all the connections and earths are clean as well to minimise any loss of power.

I have measured the 'cold' side of the bulb connections for resistance - on the 200Ω range - Zero resistance from Bulb to battery.

 

[robinbanks]

200 ohms might be a bit high to show anything other than 0 for a length of wire. You're probably talking in the region of 0.05 ohms, below the scale your meter reads to in that mode