relays

[drewboy]

it might seem stupid but can some one tell me how to wire up a relay .
my son disconected a relay for the lpg on his car and forgot to mark the wires.
it is avk with efi .
maybe some one has a diagram of how they wired there lpg in the vk efi?

 

[craigvk]

Sure,

Terminal 30: 12V or sometimes ground source. Usually the cable is thicker because this draws the most current for the device.
Terminal 85: Either ground trigger or a 12V trigger source wire
Terminal: 86: The same as above but it will say be ground if above is a 12V trigger.
Terminal(s) 87/87a: This is your output to the device(s) needing turned on/off.

So basically there isn't much to a relay. You have a 12V/ground source and an output and a 12V and ground trigger wires.
Whatever is on terminal 30, comes out at terminal 87/87a

 

[craigvk]

I should also note be very careful with gas. My relay unit is a specialised unit which has a LED (small red light) which only comes on when the car is running and it is switched in gas mode. The relay should not be energised (turned on) when the car is turned off.
If yours is similar, use the LED as an indicator to know if you wired it properly or not. I wouldn't exactly encourage people to play with the car gas units. Remember those 2 guys working on the gas for their car? They went inside for a cuppa break and the forgot to turn off their gas tank and it blew up their car, and lifted the house 1/2 a foot in the air because floating gas was ignited by their hot water pilot light. Just be careful.