Sprinter 413 CDI problem

Well estimated, I have been on the glow light of the incandescent spark plugs on for a long time, the spark plugs were very deteriorated by what I decided to replace them believing that the problem would be over but no, the light is still on and I do not know if it will be the timer and if there will be a short circuit, if so, how to check it? Thanks in advance.

The light does not turn off because this the recorded fault
would have to connect the diagnosis and erase the fault and ready unless the timer box is damaged !! With a trial lamp you would have to try if it comes to the spark plugs