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Your batteries are probably old and the plates sulphated. What you just described about the voltage going to zero wen you turn the key and attempt to start is text book typical of a battery that has voltage but no ampere’s left to provide.
Go get a new set of quality batteries and you should be good to go.
Remember what father said Shirley, When everything that is plausible has been eliminated, whatever remains however implausible has to be the answer.
Mycroft Holmes
Remember what father said Shirley, When everything that is plausible has been eliminated, whatever remains however implausible has to be the answer.
Mycroft Holmes
Dropping to 11.9V is a big drop in terms of the battery, means it's below 40% I'd say that battery is toast. Others mentioned moving the switch to parallel or emergency and see if it starts.
1st of all I want to thank everyone that offered advise. I thought that if a battery was fully charged and showing high enough voltage that that means it's good ...... So I removed all 3 batteries, swapped in 1 of the "house"batteries and it started right up.
1st of all I want to thank everyone that offered advise. I thought that if a battery was fully charged and showing high enough voltage that that means it's good ...... So I removed all 3 batteries, swapped in 1 of the "house"batteries and it started right up.
Dropping to 11.9V is a big drop in terms of the battery, means it's below 40% I'd say that battery is toast. Others mentioned moving the switch to parallel or emergency and see if it starts.
Look at post #21, he said it dropped to 11.9 on the connext screen when he turned the key, so he was attempting to crank the engine, but the connext screen was wrong because when he had the radio and blowers on they would turn off when he turned the key to crank the engine so the voltage went to 0 not 11.9, this was confirmed in post #29 when he used his multimeter to check voltage when he had his wife turn the key.
Look at post #21, he said it dropped to 11.9 on the connext screen when he turned the key, so he was attempting to crank the engine, but the connext screen was wrong because when he had the radio and blowers on they would turn off when he turned the key to crank the engine so the voltage went to 0 not 11.9, this was confirmed in post #29 when he used his multimeter to check voltage when he had his wife turn the key.
I'm not disagreeing with your comment about it dropping when you try to start, when he tried to start it dropped to 11.9 on screen and the engines didn't turn over. That is what lead to my assessment of the battery being toast. If it's a good battery yes voltage will drop as current is pulled for the starter and will attempt to turn over the engine. The voltage dropped thus the starter got current and no turn over, bad battery as not enough juice, or bad starter. But he confirmed good starter when he swapped batteries.