I have successfully replaced the glow plug and had the aux heater working fine. However, after a year or so it went again, so I replaced the plug again but this time it didn't work :25: So, I have two questions. 1. I remember reading that the diagnostic computer would need to be reset to get the heater working again (although it didn't the first time I replaced the plug.) Is this always the case? I read that disconnecting the battery for 30 mins can do this. 2. What's the best way of testing the plug? I know someone out there will have the answers - they always do :D Cheers