key was left in the on position while charging

[Catmandu]

My daughters alternator died last night. When we got it home I connected the charger to it, what I didn't realize was the key was left on while charging all night. The sound of a relay clicking was what I heard in the morning. I turned the key off and continued charging. Now when I turn the key on to first position the RPM's read 2k before it doesn't start, on action at all from ignition. Thoughts

 

[dvdswan]

I can't see this being an issue on an older vehicle. But what vehicle is it?

 

[Catmandu]

I'm sorry, I thought I mentioned that. It is a 2001 Ranger XLT 4x4.

 

[dvdswan]

Maybe @RonD will chime in or someone with more knowledge for the trucks. I would disconnect the battery and charge it. Reconnect and see what the gauge does.

I thought newer vehicles always did a self test of the dash and the gauges would sweep.

 

[Catmandu]

Maybe @RonD will chime in or someone with more knowledge for the trucks. I would disconnect the battery and charge it. Reconnect and see what the gauge does.

I thought newer vehicles always did a self test of the dash and the gauges would sweep.

I have to be up front here, I know diesel without computers,… John Deere, Caterpillar and Cummins and at that if it has Def,… I’ll try but. When I hear self check self diagnostics, I just hope thy developed a signal bypass if a tired old fart like does what I did.

 

[RonD]

Chargers typically run at 14volts so no different electrically than an alternator being on, so wouldn't hurt anything, key on or off, just less charging with key on because system was drawing some of that power

Yes, disconnecting one battery cable to charge a battery is a good idea, chargers can fail and there are things like "power spikes" in home electrical systems, and that could ruin the battery, which is bad, but better than also taking out some of the vehicles electronics as well

Clicking relay and "no action" would usually mean bad connection for battery cables, remove and clean cable ends and battery terminals, BOTH cables


When an alternator fails it usually doesn't happen instantly, so it could have been failing for awhile and that can ruin the battery
So after new alternator is installed, test engine running voltage at battery, 14.0v to 14.8volts or so is OK, drive vehicle for a few days
After vehicle sits over night(4+ hours) but before starting, test battery voltage, 12.3v to 12.8v is OK, 12.2v or lower is a failing battery, replace it

 

[Catmandu]

Sounds good, and thank you

 

[don4331]

Clicking relay and "no action" would usually mean bad connection for battery cables, remove and clean cable ends and battery terminals, BOTH cables

Clicking relay with 'no action' would suggest to me that the ignition was so worn that it was stuck in the "start" position/battery never achieved full charge.

I don't know what leaving a starter in low voltage trying to start positon would do to it.​

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I definitely charge battery overnight (slow charge setting), then check voltage (ideally with battery disconnected from everything in morning). If battery is <12V, you know where to start. If battery is good, we'll help you trouble shoot from there.