General Headlights!

[Enzo]

Hi all...currently I have on my Panda a pair of lamps like this

,
but as they produce a non exciting light I'm considering the "cool blue" bulbs, whose light's temp colour is about 4000°K...

The disavantage of this choice is the (excessive) price of the uprated bulbs...has anyone tried this on his Panda and what's the results in terms of visibility and look ??

P.S. I've already fitted the position lamps of the same line and the difference is evident...

 

[Alex]

New panda or old panda?

'Cool Blue' tinted bulbs work best with crystal style lights, conventional lights there is very little visible difference in terms of colour, but they do appear brighter. Blue side lights in my experiance don't help either.

 

[alexGS]

Hi, most of the blue bulbs are a sham and worth avoiding. You won't actually get more light - they look 'brighter' but they are tinted to achieve that effect. Tinting reduces the light output - quite simple really!

See http://www.danielsternlighting.com/tech/bulbs/blue/bad/bad.html

A much better spend of your money would be to rig up some relays and power cables direct to the battery (think of car audio amp. install kits for the components you need). This will achieve the effect of making the lights look brighter anyway, and, as a bonus, they actually will be!

I don't know anyone that has fitted relays and regretted the move. It just makes sense - it reduces the current through the light switch and the original wiring, and ensures that you have maximum power to the headlights.

How does it work? Well, you connect one side of the relay coil to the original headlight wire, and the other side of the coil to earth. There are just two more connections to make to the terminals of the relay: one to the battery via. a suitable fuse (say, 20A, use a waterproof fuseholder) and the other connection to the headlight bulb. Remember to make a good earth for the bulb as well. A car audio amp. install kit will include a suitable fuseholder, power cable, earth cable, and ring terminals (to screw onto the bodywork).

You will need another relay for high beam, but you should be able to use the same power cable and fuse holder, since low and high beam are not both on at the same time.

The left and right headlights are on separate circuits. This means you'd need another two relays for the other side (four relays total) but I would be tempted to just run the two lights in parallel off relays wired to one side of the car. This is on the limit for the relays - the relays are 10A, which is 120W. Most bulbs are 60/55W, meaning 60W for high beam, 55W for dipped beam.

-Alex

 

[alexGS]

All right, another take on the same discussion... http://www.danielsternlighting.com/tech/bulbs/blue/good/good.html

Now you'll notice that this makes reference to those Philips BlueVision bulbs... and in my Alfa 164 I have Narva 'Arctic Blue' bulbs installed. So what are they like?

They put out a nice bright-looking light - not really blue though! More like a slightly greenish-white. Are they worth it? No!

Because although my headlights look cool, they don't illuminate roadsigns properly - they look all blotchy. The range of the headlights is reduced, and the glare off wet roads is more noticeable.

So please consider before you buy blue bulbs.

I really think you will get better looks and performance by uprating the headlight circuit so that it operates at a full 12V (and maybe even a little more with the engine running). Do a multimeter test - measure voltage across your battery with engine running. Should be 14.4V. Now switch on the headlights and test between grey or green wire and black wire. I bet you're not getting 14.4V - unless you have a new Panda.

Some older FIATs (e.g. Uno) are lucky to beat 10V at the headlight. Those few volts make a BIG difference to light output... To offer something to back up my words, I did a Google search and ended up back at the same website: http://www.danielsternlighting.com/tech/relays/relays.html

-Alex

 

[Enzo]

There are two points you didn't consider:

- the "Cool blue" bulbs made by Philips or another premium brand don't produce a blue light but its colour temperature is about 4000°K, as declared on the package!This effect is not achieved with a tinted glass but with a small quantity of inert gas , which should enhance the filament's duration too :idea: .

- I measured the tension at the battery leads with the engine idling and surprise...I found a huge 17V which could explain why the batteries don't last for more than 2 years!Surely the tension at the headlamps isn't the same, but do you believe in a drop of 7Volts??

P.S. I've just won an auction on Ebay.uk for a pair of lamps, ...hope they'll arrive soon here so I can make the right considerations!

 

[alexGS]

Hmm OK... but the picture you posted shows blue-tinted glass

As for the 17V, sounds like you're very lucky... must have a 'faulty' regulator on the alternator! Keep the battery topped up with distilled water won't you?

Yeah I guess you'll get good performance with enough volts... no I don't think you'll have a 7 volt drop, you should end up with something approaching theoretical ideal 14.2V at the lights.

Good luck!
-Alex

 

[GhostWKD]

blue tinted glass is probably more the packet than the actual bulb

 

[Martiny10]

The earthing points used for the lights are prone to corrosion and consequently voltage at the bulbs can be very low.

I can't argue with the relay proposal, but a quick and dirty way to improve the lights is to replace the standard headlight earth with a feed straight to the battery, or even just onto the engine block! On my car that took voltage accross the headlight from about 8v to 11.2. I would not get much better with a relay set up. The extra 3(ish)V really does make a difference, as did adjusting the headlight beam angle.

 

[Enzo]

As for the 17V, sounds like you're very lucky... must have a 'faulty' regulator on the alternator! Keep the battery topped up with distilled water won't you?

It sounds strange a faulty regulator lets out a CONSTANT tension even if a bit high !Then I use the maintenance free batteries, and they're totally sealed so I don't know if they need water...the only help is the "magic eye" on them which changes colour depending on the tension level.

Btw I'm going to take the multimeter to check the situation... :yum:

 

[John H]

Hi Enzo.

You'll cook the battery very quickly with more than 15 volts across it -
you're right to re-measure.

Regarding the lights, the voltage across the bulb is most important, and the odd volt or so does make a huge difference as the power is voltage squared, divided by resistance.

So 10 volts to 12 volts is 44 % more power.
If you could get up to 14 volts it would be 96 % more, compared to 10 volts.

Regards


John H


Measurements from a standard Panda with 40/45 Watt bulbs:

with engine running, 14.50 volts measured across the battery.
from the earth post of battery to earth on the bulb with dip beam on, 0.22 volts.
from the earth post of battery to dip beam terminal on the bulb, 12.68 volts.
from the earth post of battery to main beam terminal on the bulb, 12.65 volts.

The bulb sees about 12.4 volts.
The wiring consumes about 2 volts.

So the total wiring and switch resistance is about 4/40 (V squared over W) or 0.1 Ohms.

Using that resistance figure for higher wattage bulbs (say a 60, for ease of calculation) you'd loose another volt in the wiring leaving you with 11.something across the bulb at best.

Unfortunately bulbs have a NTC, and draw more current if you under-run them, so you might not get as much of an improvement as you deserve with higher wattage bulbs - just a shorter life on the switches - unless you fit relays, as mentioned above.

 

[Enzo]

I've just replaced the 3 wired connectors of the lamps, and I noticed an odd thing:with the low beams on if I flash with the high beams it happens that they stay on together in the right headlamp, but in the left one the low beam seems to switch off ...I remember they're both to be on then flashing, am I right??

 

[Enzo]

I know for sure Panda has the relais for the headlamps...I hear the "click" when I turn on the switch...they're located next to the fuse box...driver's side on mine!I think it's a crime not to install the relais for high current drawing items, as bulbs, rad. fan, thermo rear window....

 

[John H]

I've just replaced the 3 wired connectors of the lamps, and I noticed an odd thing:with the low beams on if I flash with the high beams it happens that they stay on together in the right headlamp, but in the left one the low beam seems to switch off ...I remember they're both to be on then flashing, am I right??

I think you are right:
I'd expect both main and dip beams to be on when you flash, provided you had dip beam on to start with..

Regarding relays in the lighting circuits - there are none on the diagrams (Haynes upto 1993) I've just looked at for the post 1986 models.
If you have some, they are a modification, or Italian specification is better than UK.

Regards


John H

 

[Enzo]

Wow...the problem when flashing has been solved, just 2 wires inverted :bang: !Regarding the relais I took a look again at them and it seems an handcraft job...as they're not fixed anywhere!