Offroad-Express

Im wanting to find out what out the puts are from the pre heat that send a signal to the relay.

I have done a fair bit of googling and nothing that helps.

Wanting to wire a light that actually matches what is happening, not the unreliable dashboard indicator light.
Cheers, Paul.

Grab a multimeter, test for voltage once black-red, once black-yellow when the key is turned, it should show up voltage for a few seconds (while the plug "glows") then drop out.

I don't know why the dash light should be unreliable as it would be doing the same thing, surely?

In some vehicles, the glow plugs are still operating after engine start, albeit at a lower voltage. This helps the engine run smoother while things get a bit of heat through them to allow normal running on it's own. In these cases, the dash light only indicates that the glow plugs are on before start.

The simplest way, would be to throw a volt meter across the glow rail and an earth point somewhere for actual indication for what is going on.

Thanks guys,

The dash light times out after about 5 seconds, the relay goes out after about 15.
From what I can read they have different outputs from the timer.

I will check with multi meter as suggested, cheers.