05 Expy No Crank No Start No Communication

[pastorjeep]

My wife's car had a dead battery a couple of mornings ago. I jumped it and no help. I tested the battery with DVM and it was at 6.5v. I told my wife we need a battery. Pull battery out and decide to test again and it reads 12.45. Hmm, so I trickle charge a few hours and it is 12.95. Back in the car it goes. Pretty noticeable sparking when hooking up cables. No crank, no dash lights, test battery 5.75v with DVM leads on battery clamps but 12.4 if DVM leads are on battery posts. Losing 7v at the terminal! Pull off negative cable to do a parasitic draw test and get .22 Ma. Go to fuse box to start pulling fuses and I am getting a constant clicking sound. with finger on each relay can't feel it, so I removed all relays and still clicking. The voltage at each end of the battery cables is the same 5.75. I have never seen anything like this. What could be shorted that badly? Internal fuse box short?

 

[Yupster Dog]

Take the battery to get tested at an auto parts store. your battery can read 12v and still be bad. It needs to be load tested.
After you have reliable power then diagnose. otherwise you could be chasing your tail.

Note: Any starter batteries loose reliability and strength when they loose volts that low. They are meant to be at full charge at all times.

A Voltage Drop Test will tell you if you have good connections and cables for power and ground.

 

[pastorjeep]

Did the voltage drop test and have the same at each end. I decided to remove one harness wire at a time and see if the voltage jumps back up. Removing the alternator and then starter wire had no effect. Removing the fuse box wire caused the voltage to go back to normal. I think something is shorted in the fuse box.

 

[Yupster Dog]

Did the voltage drop test and have the same at each end. I decided to remove one harness wire at a time and see if the voltage jumps back up. Removing the alternator and then starter wire had no effect. Removing the fuse box wire caused the voltage to go back to normal. I think something is shorted in the fuse box.

Check this thread out
Another fuse box replacement ....