Ideas and advice please

[Anubisxc70]

2004 XC70 D5 awd

Hello to all.
I have a few things that i would apreciate someone could give me some help and advice.

My car has the glass headlights. I have all bulbs working and they are new ( H7 i guess) but my headlight are yellow and weak at night, not much light. What can i do. I dont want to modify anything or have any MOT issues so what can i do to have decent headlights light. Ideas PLease

My exhaust, guess is the original one, is getting old. I have seen a read that if we change it for non volvo thesound gets loude etc etc. I saw on ebay some for 130 pounds, are those any good? Any advise?

I have the dog guard, but one of the gas struts is dead so the thing keeps falling. Where can i get replacements, part number, can they be fixed?

Many thanks

[bkulcsar]

Just plug some H7 Osram Night Breaker Unlimited bulbs in. They are very bright, but don't have the longest life...

[petey]

Before you go cracking into a technology solution for a preparation problem, please consider the voltage drop across the supply and earth before you go wanging pounds at a simple wiring problem.

[staffy460]

dog guard gas strut easy to do , got one from ebay £20

[Anubisxc70]

Originally Posted by petey

Before you go cracking into a technology solution for a preparation problem, please consider the voltage drop across the supply and earth before you go wanging pounds at a simple wiring problem.

Thank you for reply. What you mean........?
I checked all the ground wires all are connected and clean. i have checked my cables and re tape them, all is good. What to look for Petey?

[petey]

Originally Posted by Anubisxc70

Thank you for reply. What you mean........?
I checked all the ground wires all are connected and clean. i have checked my cables and re tape them, all is good. What to look for Petey?

You’re looking for the voltage across the bulb. When the car is new, all the wires, connectors and earth points have good low resistance connections. As the car ages the voltage drop at every connector goes up and before you know it you have a lower voltage than you expect.

So if you measure the voltage across the battery (the battery itself, not the satellite connections under the bonnet), that’s going to be the best that you can get. You measure the voltage across the bulb connector when the lights are on; is it the same as the battery? It probably won’t be, so there is a voltage drop somewhere along the line.
You then measure the voltage drop between the -ve side of the bulb and earth.
Also between the +ve side of the bulb holder and a good battery +ve.
You might find that one or other side of the bulb is not receiving the full potential and cleaning even small levels of corrosion in a connector or earth point can make huge differences to bulb brightness.

[jgjones095]

Originally Posted by staffy460

dog guard gas strut easy to do , got one from ebay £20

I used these at £1.80 each.
https://rover.ebay.com/rover/0/0/0?m...2F281309954428

See thread here

https://www.volvoforums.org.uk/showthread.php?t=282947

[Brendan W]

To add to Petey's suggestion...
I would do this test with the bulb out of the headlamp and the motor running. Measure the voltage between the bulb pins with the lights on.
The battery could be up around 14 V but most importantly, stable. With the motor off the battery voltage falls with load on and by the time you run back to the front of the car it has changed.
Take an extreme example and suppose you find only 12 V across the bulb pins.
Two volts have gone missing. Now put the meter between the earth pin side of the bulb and a good earth point on the car. The voltage should be close to zero. If it is the culprit is on the other, supply, side.
Cleaning pins in plugs, bulb holders and less frequently, relays can get you back most of the drop. Realistically you are doing quite well if the bulb voltage is only half a volt below battery.

[staffy460]

Originally Posted by jgjones095

I used these at £1.80 each.
https://rover.ebay.com/rover/0/0/0?m...2F281309954428

See thread here

https://www.volvoforums.org.uk/showthread.php?t=282947

well done id of saved £18 if i had of known

[ThomasG]

Originally Posted by Brendan W

To add to Petey's suggestion...
I would do this test with the bulb out of the headlamp and the motor running. Measure the voltage between the bulb pins with the lights on.
The battery could be up around 14 V but most importantly, stable. With the motor off the battery voltage falls with load on and by the time you run back to the front of the car it has changed.
Take an extreme example and suppose you find only 12 V across the bulb pins.
Two volts have gone missing. Now put the meter between the earth pin side of the bulb and a good earth point on the car. The voltage should be close to zero. If it is the culprit is on the other, supply, side.
Cleaning pins in plugs, bulb holders and less frequently, relays can get you back most of the drop. Realistically you are doing quite well if the bulb voltage is only half a volt below battery.

Engine running- yes
Bulb out- no.

Voltage drop increases with the load.

For example- on same cable and connector, same battery etc, if you test across a 5W bulb, you'll get let's say 12.8V, but if you replace bulb with a 50W (still only example) it may well be below 12V.

So test that with bulb in.