Fault code P067000

Hi. I have the orange engine management light on. I scanned the codes and have come up with P067000 'glow plug module control circuit active/static'. I've replaced the glow plug control module and cleared the code but the fault comes back after a few days. Any suggestions as to what else this could be? I've checked the battery (it's less than 6 months old) and it's reading 12.6v so I don't think it's this. I've also changed the glow plugs since they were 10 years old/ 90,000 miles. 1.6tdi cr. Thanks in advance.