2003 w203/cl203 c220 cdi glow plug
 

Hi Guys

the coil symbol in the dashboard of my 2003 w203/cl203 c220 CDI coupe car is constantly turned on

does that mean that one/some of my glow plugs is/are defective? i can still start the engine in cold morning with no problems

if they are i am thinking of changing them myself but is there a way to actually identify which glow plugs are not working before physically removing them and then testing each separately? like some hidden option in teh dashboard :)

or could this be an electronics glitch? sometime i get these weird electrical errors that disappear after sometime, however, this error (the coil symbol) has been on for some time now 4-6 months

your help is appreciated

Haitham