Dim Dash Lights

[DK161]

Hi
Can anyone tell me why when starting my toyota in the morning i turn the key to position 1 then ignition on but the dash lights are so dim then a second later they come on bright and then the glow plug light will come on at the same time. And then i can start it. But some times when turning ignition on the dash lights just flicker. I then turn the key off and on again then its normal.?

[sledge]

loose wire or conection on the back of the cluster

[DK161]

Thanks will give it a check!