eber / battery voltage

[markysparky81]

Hi there got a 81 westy joker lhd diesel had vehicle for nearly 2 years the last 4 months or so eber wont fire up unless on a hookup or engine running. Got 2 lesure battrys under front seats and start batt in engine bay, tested both leisure batts ok even replaced one checked with meter alternator charging both batts, both read 12.7 engine off, 13v engine on. 12volt light on green on sink unit soon as eber powered up engine off amber light fading into red and eber fan runs but does not fire up could glow plug be faulty drawing too mutch power any info please

[Oldiebut goodie]

Maybe your wiring isn't hefty enough and is causing too much of a voltage drop.Check the voltage at the battery as you are firing it up and at the heater. Have you tried with the new battery alone - if the other one is duff it will bring the new one down. If the glow plug were faulty I wouldn't have thought that it would fire up at all.