Am I Missing something?

[bumble bee]

My rear lights are a bit dull when the van is on its own and even worse when i have the trailer hucked up ive cleaned up the 2 earth wires under the coil cleaned the christmas trees at the front and cleaned up the towbar earth which is behind the "junction box" in the engine bay. ive just put a new socket for the trailer lights on, new crimps on the trailer connections. when i first got the van the lights were realy realy dull i cleaned up the formentioned earths replaced the relay for the indicators and they are better now but i saw another T25 with much much better lights than mine. its like ive put a 24V bulb in (i havent by the way) so im a bit lost realy i have 12v ish when ive tested at the lights its passed its MOT but it aint right. any ideas??

[BOXY]

Have you tried cleaning up the bulbs, holders and reflectors? What voltage are you getting if you put a multimeter across the centre of the bulb holder and an earth point?

[California Dreamin]

The secret to brighter lights could be 10 watt side lights and not 5 like the ones you have......perfectly fine to fit these even tho the bulb holder probably says 5 watt.

Martin

[kevtherev]

Are the brake lights / indicators dull too?

[bigherb]

Like boxy said first check you have the correct voltage at the rear lights. Check it at the rear of the bulb holder with the bulb still in place, the circuit has to be under load to get a meaningful reading. And check you have the correct 10w bulbs fitted not 5w.

[kevtherev]

Rears are twin filament 10/21 watt as standard

[bigherb]

Rears are twin filament 10/21 watt as standard

VW used seperate tail and stop light bulbs.

[kevtherev]

so they are... I have had leds on our van for so long I forgot.

[CovKid]

To be honest, the rear lights never were that good to start with. You could try LED equivalents although if you switch indicator bulbs to LED you'll need to change the flasher relay to one suited to LED lights or it won't function.

[bumble bee]

Are the brake lights / indicators dull too?

to be honest i no the lights are rubbish the side lights are dull ish but ok the brake lights are ok i think but its the indicators and when i connect the trailer up that worry me are they are all pants when the trailer is connected and just realy the indicators when the trailer is connected.

[kevtherev]

When you say "new crimps" on the connections I hope you don't mean scotchlocks... They're rubbish.
Soldered joints or proper male female spades/bullets should be used
are the trailer earth connections OK
that might be the problem.

[bumble bee]

When you say "new crimps" on the connections I hope you don't mean scotchlocks... They're rubbish.
Soldered joints or proper male female spades/bullets should be used
are the trailer earth connections OK
that might be the problem.

No they are definatly crimped I dont like them scotchlocks thats what I've taken off. I had a brain wave yesterday that it could be the earth lead to the battery as it sits on paint I think so im gonna investigate that tomorrow

[bumble bee]

AH HA, ive had a break through im 99.5% certain that it is 1 of the following: alternator, battery or earth lead from battery to the vehicle as tonight when i connected the trailer up to the van i had nothing on except 1 indicator and it was as bright as the north star!!! well prob not that bright but you get the idea and the more i put on like radio, lights (that was a killer) fan ect ect the duller they got. thanks for every1s help im nearing the end of a dull tunnel now.