The battery pack would not stop blinking red on the battery pack charger, no matter how long the battery pack sat on the charger. This mean that the Craftsman 19.2V Diehard battery pack would not accept a charge. Heard of a trick to start the battery pack with a jump start from another battery pack, so giving that a try before discarding the battery pack.
Before jump start the battery pack, had to figure out which terminal was positive or negative. There were no markings on the battery pack case to indicate which terminal was which. There were also no markings inside the port where the battery pack connect to the battery pack charger. This made the jump start process more more complicated than it should of been.
To examine the battery pack more closely, had to open the battery pack to view what was inside of it. Once I opened the battery pack, I could see the wiring. It was then possible to determine which pin was which. The pin that connected to the red wire in the battery pack were the positive terminal. The pin that connected to the black wire in the battery pack was the negative terminal.
To confirm the previous findings, used a multimeter to test the voltage output of the dead battery pack. The voltage indicator on the multimeter read 0 volts. There was no voltage coming from the dead battery pack. A good battery pack that was tested beside the dead one registered approximately 19.2 volts, the voltage that a fully charged battery pack should register. This confirm that the battery pack is completely flat.
Inspecting the battery pack
To examine the battery pack for damage, opened it up to access the battery cells. As soon as I opened the battery pack, it was clear that there was corrosion on the battery cells. There were also dent and rust spots on the battery pack.
This particular model uses 11865-size cells instead of the more common 18650 cells. The corrosion alone told me that the battery cells were beyond saving.
At this point, I would have to replace the battery cells with new 11865 replacement cells. I would need the spot welder to join the two battery packs together at the various connection point. I figured that replacing the cells was my only real option. I did, however, try the jump-start trick with the thought that perhaps it would help the dead battery pack to at least start up the motor itself.
To perform a jump-start on this battery pack, I had to first gather two battery pack items. I found it best to place the two battery packs beside each other and use alligator clip test leads to connect the good battery pack to the dead battery pack. I connected the positive terminal of the good battery to the positive terminal of the dead battery. I then connected the negative terminals of each battery pack together. It was important to make sure I connected the positive to the positive and the negative to the negative; incorrectly connecting the two sets of terminals would of destroyed the good battery pack.
After connecting the two battery packs together with the alligator clip leads, I allowed the good battery to remain connected to the dead battery for around fifteen seconds. During this time, the good battery was suppose to transfer enough electrical charge to the dead battery to start the motor. During this time, it is important to watch the leads for any heat or smoking of the wires. Smoked leads indicate that the lead is too thin to allow this much current to pass through it. Any smoking during this jump start process would require me to immediately disconnect the leads.
After fifteen seconds, I disconnected the leads from the two battery packs. I attempted to start the vehicle with the dead battery pack, but unfortunatly, I had no luck. The battery pack still did not have any voltage, nor would it charge when I placed it back upon the vehicles battery charger. The red light continued to blink in the battery pack, indicating that I had not been successful in jump starting the vehicle. Thus, the cell within the battery pack had completely failed, and I would have had to purchase a new battery pack for the vehicle.
