flat battery?
Moderator: Moderators
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Anonymous
I only mentioned resistance of earth leads because no matter how good the + to the starter solenoid and starter motor is the motor only works to full torque when it sees a full 12 volts across it and that 12 volts can drive a current through the motor.
now if the earth lead from the engine to the body is the only return lead to the battery and if it has a massive Resistance (i.e is too thin is too corroded or is not bolted down) it will cause the starter not to start the car, it sounds like a flat battery and yes the dash lights will dim because a motor that stands still still draws a bigger current than one that spins.
the resistance of the motor and earth lead dictate the current that flows and the current that flows dictates the torque of the starter motor and its ultimate sucess or failure to start the car.
i.e you get a click but no action with no current flow.
Was this a flat battery scenario or a knackerd battery scenario??? The one thing reported each time was everything worked for a bit but the car wouldn't start
how many of us have bought a battery or a new starter when we haven't actually needed to do anything other than sort out connections between battery solenoid starter and earth?
I was outlining an alternative scenario that fits with
car won't start
but doesn't depend on identifying if the new battery is knackered, it shouldn't be, its new, the meter reading was obviously wrong.
DaveR has already outlined a nice easy way to establish charging or short.
the rest of the post was to establish if Mr dodge was having difficulty with any of the issues i have had experience with that caused my car not to start or my battery to go flat.
now all cars are different and granted the issue will probably not be any that i listed but investigating those kinds of things gets you into the mindset that causes you to spot the real issue.
it was an alternative to my original post which was
doesn't matter how old or new the battery is
over charge it or run it flat
its shagged....
which helps nobody
I think it was more use in its new form
now I'm not suggesting that Mr dodge do anything that i have suggested. I wouldn't be so presumptuous as to believe anyone would jump to my command but...if anything i have said helps then my work has paid me well for something they don't benfit from
.
Dave
now if the earth lead from the engine to the body is the only return lead to the battery and if it has a massive Resistance (i.e is too thin is too corroded or is not bolted down) it will cause the starter not to start the car, it sounds like a flat battery and yes the dash lights will dim because a motor that stands still still draws a bigger current than one that spins.
the resistance of the motor and earth lead dictate the current that flows and the current that flows dictates the torque of the starter motor and its ultimate sucess or failure to start the car.
i.e you get a click but no action with no current flow.
Was this a flat battery scenario or a knackerd battery scenario??? The one thing reported each time was everything worked for a bit but the car wouldn't start
how many of us have bought a battery or a new starter when we haven't actually needed to do anything other than sort out connections between battery solenoid starter and earth?
I was outlining an alternative scenario that fits with
car won't start
but doesn't depend on identifying if the new battery is knackered, it shouldn't be, its new, the meter reading was obviously wrong.
DaveR has already outlined a nice easy way to establish charging or short.
the rest of the post was to establish if Mr dodge was having difficulty with any of the issues i have had experience with that caused my car not to start or my battery to go flat.
now all cars are different and granted the issue will probably not be any that i listed but investigating those kinds of things gets you into the mindset that causes you to spot the real issue.
it was an alternative to my original post which was
doesn't matter how old or new the battery is
over charge it or run it flat
its shagged....
which helps nobody
I think it was more use in its new form
now I'm not suggesting that Mr dodge do anything that i have suggested. I wouldn't be so presumptuous as to believe anyone would jump to my command but...if anything i have said helps then my work has paid me well for something they don't benfit from
Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
dave 999 you could be right it could be something more simple than a flat or knacered battery but im going on what the very nice AA man said after he tested etc it very early saturday morning he was certain that the original battery wasnt capable of holding a decent charge, he didnt actually check any leads for damage that i can remember although he did have a multimeter out doing stuff, i couldnt see what he was testing or doing as i was in the car turning the ignition on and off at the time
ticking away the moments that make up a dull day, you fritter and waste the hours in an offhand way.
no car - buts its gotta be a mopar!
no car - buts its gotta be a mopar!
don't worry mate
it will be a simple thing just awkward to find and i've probably clouded the issue by introducing too many could be s
do daves tests first see if a current is being drawn with everything turned off.
also nice new earth strap will assist in all engine electrical activities starting:- motor and solendoid operation, and ignition.
Its a vital part of both circuits.
Dave
it will be a simple thing just awkward to find and i've probably clouded the issue by introducing too many could be s
do daves tests first see if a current is being drawn with everything turned off.
also nice new earth strap will assist in all engine electrical activities starting:- motor and solendoid operation, and ignition.
Its a vital part of both circuits.
Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
here we go then latest update, ive fitted the new earth lead and still got the same problem, dim lights on dash etc when i turn on the ignition, so this is what i have done,
i disconnected both battery leads and checked the voltage of the battery (using a different meter) and it reads 12.94v, the battery hasnt been recharged since before
i attached the + lead to the + terminal on the battery and checked the amps between the - lead & the - terminal and it reads - 10.8 fluctuating to - 12.1,
i then disconnected the + lead and connected the - lead to the - terminal and checked the amps between the + terminal & the + lead and it reads 12.2, are the amp readings correct? as im not sure what figure i should have expected,
so from this information can i assume that there is a "leak" of some sort somewhere,
ive disconnected both terminals from the battery so as the battery will not discharge
i disconnected both battery leads and checked the voltage of the battery (using a different meter) and it reads 12.94v, the battery hasnt been recharged since before
i attached the + lead to the + terminal on the battery and checked the amps between the - lead & the - terminal and it reads - 10.8 fluctuating to - 12.1,
i then disconnected the + lead and connected the - lead to the - terminal and checked the amps between the + terminal & the + lead and it reads 12.2, are the amp readings correct? as im not sure what figure i should have expected,
so from this information can i assume that there is a "leak" of some sort somewhere,
ive disconnected both terminals from the battery so as the battery will not discharge
ticking away the moments that make up a dull day, you fritter and waste the hours in an offhand way.
no car - buts its gotta be a mopar!
no car - buts its gotta be a mopar!
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Anonymous
With the engine 'off' and all ancilliaries 'off' you shouldnt be loosing anything. Everything should be open circuit (unless you have put in an aftermarket clock / stereo which continuously draws power but that would be a negligible amount).
It would seem that you have a short circuit somewhere. I agree with Dave R. You might have a serious wiring problem somewhere.
A very easy thing you could try, is unplug all the bulkhead connectors from the block and try testing again. If the drain is still there, the problem is unlikely to be in the rear light harness, the front light harness, or the engine harness. That only leaves the starting circuit and the dash harness. If the draw disappears after the diconnections, pkug em in one at a time, testing in between abd you may identify the area you need to check out first.
We did say short circuit before. A continuity test isnt going to help in this situation very much.
It would seem that you have a short circuit somewhere. I agree with Dave R. You might have a serious wiring problem somewhere.
A very easy thing you could try, is unplug all the bulkhead connectors from the block and try testing again. If the drain is still there, the problem is unlikely to be in the rear light harness, the front light harness, or the engine harness. That only leaves the starting circuit and the dash harness. If the draw disappears after the diconnections, pkug em in one at a time, testing in between abd you may identify the area you need to check out first.
We did say short circuit before. A continuity test isnt going to help in this situation very much.
here are the pictures of the readings taking this morning before 7!! not the clearest of pictures as they were taken on my mobile phone, as soon as you turn the ignition to start the engine the lights go out but if you take off the battery cable for a few seconds and reattach it again the lights are nice and bright again
the meter is set to .20 for the volt reading and .2000u for the amps reading
ive got a short video taken on my fone of my attempt to start the engine but i dont know how to attach it as its a 3gp file and isnt listed in allowed attachements???
the meter is set to .20 for the volt reading and .2000u for the amps reading
ive got a short video taken on my fone of my attempt to start the engine but i dont know how to attach it as its a 3gp file and isnt listed in allowed attachements???
ticking away the moments that make up a dull day, you fritter and waste the hours in an offhand way.
no car - buts its gotta be a mopar!
no car - buts its gotta be a mopar!
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Anonymous
Here is an idea.
Charge the battery. Make sure you have 13(ish) volts on the battery without it connected to the car. Attach it to the car. Start the car. Check, as Dave mentioned, that you have approx 14 to 14.5 volts across the battery while the engine is running. Stop the car. Measure the battery voltage again.
Disconnect the battery from the car.
Leave it overnight.
Next day, check the battery voltage again (it should be the same as the day before).
Connect battery and start car.
If the voltage in the battery is closely the same as the day before, and the car starts, you have something pulling power out of the battery while the car is not in use.
Refer then, again to Dave's first post, and Clive's above about isolating various electrical sub components to track down the fault.
Other things to do for elimination are: remove interior bulb, remove glovebox bulb, remove boot bulb just in case one of those is staying on, or slightly on.
Charge the battery. Make sure you have 13(ish) volts on the battery without it connected to the car. Attach it to the car. Start the car. Check, as Dave mentioned, that you have approx 14 to 14.5 volts across the battery while the engine is running. Stop the car. Measure the battery voltage again.
Disconnect the battery from the car.
Leave it overnight.
Next day, check the battery voltage again (it should be the same as the day before).
Connect battery and start car.
If the voltage in the battery is closely the same as the day before, and the car starts, you have something pulling power out of the battery while the car is not in use.
Refer then, again to Dave's first post, and Clive's above about isolating various electrical sub components to track down the fault.
Other things to do for elimination are: remove interior bulb, remove glovebox bulb, remove boot bulb just in case one of those is staying on, or slightly on.
