Car charging NOT working

[Guest gbjbasdw]

Got a real weird one for you today, guys !

 

I have a car charger plug for the car. It's rated at 1A and 2.1A output in each of the two output sockets respectively.

 

It works perfectly charging my tablet whose wall charged says 2.1A and also with a ZTE Blade Q mini phone so the outputs from the charger plug are OK I reckon.

 

I have 3 USB charging cables - each works ok with the ZTE Blade Q mini phone so I reckon the cables are all ok.

 

If I plug the San Diego into my PC USB output it says it is charging ok - this happens with all three cables - again proving the cables are ok.

 

BUT
 

When I plug the San Diego into the car charger it does not come up with "Charging" !!

 

I can't see any earthly reason why this should be happening as I know that the car charger and cables are all ok.

 

Anyone got any ideas ??