Need Verification on Electrical issue

[kitsapcuda]

Car does not start.  Acts like no power from battery.
Specs-

11.7 V from battery, Red Wire at harness and red wire from harness to ignition

Specs with key turned to Run position-

Same as above for Red wire
4.7 V on Brown from ignition to harness, on other side of Harness at Firewall and on Dark Blue/Brown at ballast at on + side of coil.

7.0 V on other side of Ballast from ECU and Start postion.

If I pull the Dark blue/Brown off of ballast, the other side goes from 7.0 to 8.0 V.   


I suspect that the 4.7 for the coil is not enough as it tries to start on first crank, then you get the sound like starter is not getting enough juice and that battery is almost dead.

What is best way to trace problem from here, assuming that I have a problem with not getting proper 9.0V to the plus side of coil?   Possible short in key switch?

Thanks.

[422STROKER]

Did you charge the Battery?  It should be 12.6V or so to begin with.

Tom

[kitsapcuda]

The 11.7 V is after leaving it in run position for a bit, so I have a drain/short going on.  If I add booster to battery, then voltage goes back up to normal, and all figures stay the same relatively, just that they go up no more then 1V across the board.

[GoodysGotaCuda]

were to checking voltage to the coil while cranking? it will bypass the ballast resistor when the key is in "start" giving full battery voltage..

and your battery voltage is about a volt low to begin with.

[kitsapcuda]

Did not check voltage when cranking.  Since it tries to go, then gives indication that battery is low, I started checking voltages when only in run postion.  Does not sound or do good when cranking and getting funny sounds and screeching noises.
Reading other posts, I read that you need to have at least 9V in run position to run side of ballast and + of coil to be ready before you crank over to start position, so I figures I have a short somewhere.

[GoodysGotaCuda]

Are you getting a consistent crank out of the starter? If not, and it's making noises. You need to look into the starter, or the starting circuit, rather than the ignition side. Get a solid, consistent crank, before looking at the ignition.

Is this a "all of a sudden" problem? "just bought the car and..." problem? or?

[kitsapcuda]

Had a problem a few weeks ago when I started up for a spring drive.  At that time I had a short under dash, but corrected that.
Started is about a year old. 
I guess next it to bypass ignition and go from battery to postive side of coil.....  I have heard of this test before.  Is this the best test or go battery to ballast?

[MEK-Dangerfield]

Is your battery good? Wether you have enough voltage at the coil or not, should not make the engine turn like the battery is weak. I'm saying bad battery, or the battery doesn't have a good clean connection to your starter or engine block. Check out your cables.


   Mike

[73Chally]

My guess is the battery.  If it drops to 11.6 with the key in the run position, then you could have a weak cell.  If it was me I would pull it out and take it to the store and have them run a test on it.  If the battery tests good, then you need to start looking at the + and - cables off the battery, then on to the ballast resistor, etc.

[kitsapcuda]

success -
Tried to start with 11.36V on Battery - same problem
Add battery booster and get 11.63V at Battery, and it starts up
Replace battery with boat battery for temp fix and have  12V and car started right up.

Appears my 3 year old Authentic mopar battery is bad. 

So final question, is that possible? Any seen this?

[422STROKER]

I have seen many threads on the resto batteries failing quickly.

Some guys seem to run regular batts ans swap the resto in for the show.

Tom

Glad you got it figured out.  Did you check the voltage when it was running?  Just to check the ALT.

[GoodysGotaCuda]

success -
Tried to start with 11.36V on Battery - same problem
Add battery booster and get 11.63V at Battery, and it starts up
Replace battery with boat battery for temp fix and have  12V and car started right up.

Appears my 3 year old Authentic mopar battery is bad. 

So final question, is that possible? Any seen this?

Very possible. And you should maybe pickup a better charger or booster. 11.6 volts is still a full volt low than a charged battery. Jumping off another car will atleast give you around 13v to work with.

[73Chally]

Glad you got it figured out, but I wouldn't drive it around with the boat battery, since it's a deep cycle battery.  I'm not for sure but I know they are designed to charge at a slower rate, and there could be some issues of over charging with it running in the car.