I noticed recently that the ignition light has been glimmering intermittently whilst driving and on Sunday, during a trip out where I got stuck in traffic for a long period with the radiator fan on, the engine died. The AA came out, said I had an alternator issue, gave the battery a quick boost and I was able to get home. I've now checked the battery voltages. Whilst idling, the voltage at the battery is only around 13v suggesting the alternator isn't working. However, if a rev over 1500rpm, the voltage reads 14.2v which I believe is about right. Does this mean the alternator is fine and I just need the alternator to run quicker when the engines idling? I can't see what type of alternator I have but it's on a 2007 Duratec 2.0. It's a 3 month old Banner battery. Thanks in advance. Tim