Wiring a trailer

Anthonyk2010

I'm after replacing the wiring on my trailer lights and i have hit a couple of problems.

The indicators are the first problem, one minute they work the next minute nothing. I stuck a screwdriver inbetween the bulb and the termanels and they work fine,when i remove it bulb stop blinking

Could this be a ground problem or is the bulb unit finished.

Next the brake light dont work at all, no idea why.
I have checked all the wiring and it looks fine but i'm not sure how it test if there is power coming through.
Can it be done with a multimeter?

Why is there no neutral wire, how is the circuit complete

jimmyw

Probably just the spring loaded contacts at the bottom of the holder that the bulb bears against is bent too far.Turn off the power and bend them a little with a screwdriver with the bulb out.Check the same contacts, or anywhere you can get the meter probe into the wire on the brake lights with the power on with a multimeter on the 20 volts scale and earth.There is no neutral wire with car electrics, just two, one from the batt live to the component and one going back to the batt earth.

Anthonyk2010

jimmyw wrote: »

Probably just the spring loaded contacts at the bottom of the holder that the bulb bears against is bent too far.Turn off the power and bend them a little with a screwdriver with the bulb out.Check the same contacts on the brake lights with the power on with a multimeter on the 20 volts scale and earth.There is no neutral wire with car electrics, just two, one from the batt live to the component and one going back to the batt earth.

Thanks jimmy. So the white(earth) wire acts as a neutral.

Regarding the multimeter, i turn it to 20 place one contact on the wire and the other on the white wire(earth wire). What will come up on the multimeter if i have no problems?

jimmyw

Yeah one probe on one of the contacts, and one to the earth wire of the light or any metal part nearby thats not painted.If there is power you will get 12-13 volts.Remember to get someone to hold the pedal or jam something on the pedal.

Anthonyk2010

The brake bulbs have two elements in them and two small knobs on each side of the base of the bulbs, does it make a difference which way the bulb fits in.

I still can't get the brake lights to work. Everything else is working fine.

jimmyw

Yes it does matter which way they go.Will only work right one way, otherwise wrong filament will work or not. Is there power getting to the contacts?

Oh you mean the base, I was thinking about the pips on the side.They should make contact with the contacts in the holder.

Anthonyk2010

jimmyw wrote: »

Yes it does matter which way they go.Will only work right one way, otherwise wrong filament will work or not. Is there power getting to the contacts?

Oh you mean the base, I was thinking about the pips on the side.They should make contact with the contacts in the holder.

Ya jimmy, it's the pips I'm talking about, does it matter which way they are turned or will they make contact once there in.
I noticed that one pip is higher then the other and thought that may one is not making contact.

Have not checked the power yet.

jimmyw

Right the side pips are only there to hold in the bulb not to make contact with the power source.The power contacts are at the bottom of the bulb.
Yeah the bulb will only go in one way for to work.



Red arrow is the power contacts, blue arrow is the holding pips.

Anthonyk2010

jimmyw wrote: »

Right the side pips are only there to hold in the bulb not to make contact with the power source.The power contacts are at the bottom of the bulb.
Yeah the bulb will only go in one way for to work.



Red arrow is the power contacts, blue arrow is the holding pips.

Thanks jimmy.

Anthonyk2010

Got it sorted jimmy, it was a blown fuse. Simple little thing.

jimmyw

Great, glad you got it sorted.What was wrong with the indicators?

Anthonyk2010

jimmyw wrote: »

Great, glad you got it sorted.What was wrong with the indicators?

Think all the connections in lights were old and corroded, i got new ones and soldered everything.