teknopete

As above, does any1 know what the minimum required voltage is to start a classic WRX ? I`m showing 11.9v but she`s not happy

Thanx
Pete

LB4

11.9 volts sounds enough, but check what it drops to when cranking over, it shouldn't go much below 9 .. if it does then the battery either needs a good charge or has had it.

teknopete

Thanks LB, I`ll give it a check

Pete

Forester_GP

Pete, 11.9 V is less than 50% charge, so you'll get starting problems, test & compare according to the following:

State of Charge 12 Volt battery Volts per Cell
100% 12.7 2.12
90% 12.5 2.08
80% 12.42 2.07
70% 12.32 2.05
60% 12.20 2.03
50% 12.06 2.01
40% 11.9 1.98
30% 11.75 1.96
20% 11.58 1.93
10% 11.31 1.89
0 10.5 1.75

Regards,

George

teknopete

Thanks George,

I`m on the case now.

Pete

Forester_GP

Pete, you're welcomed, just a note, the table above is for a "setlled" floating voltage @ 25C (-20% capacity @ freezing) after half an hour or so after charge applied. As noticed in your other thread and depending on charger used (how intelligent or regulated?) you should measure 14.1 - 14.7 V tops, while charger is connected on a fully charged battery.

George