Originally Posted by
Yendor
Hopefully they stay on longer then 6 seconds when the engine is cold.
If there not staying on long enough you might need to look at installing the manual switch in the dash. You only need a momentary push switch and some wire to do this. You can still use the original relay.
The glow plug light flashing is just telling you that there is a problem with the after-glow, because it's disconnected. It will keep flashing until the engine temperature heats up to a certain temperature or you drive the vehicle above a certain speed.