When is a flat battery not a flat battery? When it’s a problem with glow plugs. OK, that’s a bit simplistic but frequently people breakdown with what they think is a battery problem, only for it to turn out to be the glow plugs that are at fault.
The reason is that diesel engines use these heaters to help them start. In warmer weather they’re not as necessary. However, when the weather gets cold, glow plugs are vital. That’s why in November 2017, the number of call outs Green Flag attended for glow plug problems rose by 112 per cent. Read on to find out what the problem is and how you can diagnose it.