Fuse wouldn’t blow right away. 7 Reasons Your Car Battery Is Not Charging It's running til the battery charge is drained. This power is used to charge the battery, and to provide all of the power necessary to run things like the headlights, interior lights, the radio, and all other accessories. I have a diagram for the charging system, can you tell me the color wires and where they could be shorted? Continuity is good between positive terminal and alternator B terminal and battery isn't being charged; BUT if I take off the charge cable from the B terminal it's getting 14V, put it back on it's back down to 12.2 while running (new battery as well). Battery and Brake Light causing alternator Not to charge Battery for Toyota camry 1988 3sfe Last Post RSS. Your vehicle’s charging system, however, … If only one or two diodes have failed, the alternator may still produce enough current to meet the vehicle’s electrical needs, but it may not be enough to keep up with higher loads or keep the battery fully charged. Replaced the alternator and battery. The car does not want to hold a charge and the alternator does not want to charge the battery. It takes only a few minutes and will help you locate problems in the circuit’s wiring that may not be visible at plain sight. If the alternator charges when doing this, it is a faulty new PCM/ECM. Replaced alternator with Carquest 14105A and everything went on easy but it isn't charging. This time it should be at least 142 volts if the alternator is healthy and charging the battery. 22/02/2021 5:00 pm. I haven't put an amp-meter on the alternator to find out. Also replaced the pig tail going to the alternator it was brittle and loose. If the alternator does not charge when doing this, then it is likely a faulty new alternator or a faulty/missing input to the alternator (power or ground supply) provided that green wire is not broken going to the alternator. U don't have to pay a mechanic to check charging system, take ut Auto zone and they will check it free of charge. When your alternator is in good working condition it constantly maintains bright … The voltage on the lower right tab is 14.46v. If it is charging and light still on, check fuses or loose wires from alternator … As soon as you turn on the radio, or climate control the car looses all charge. The alternator is a key component in running the electrical systems in your car. 0. On the upper right tab it's now 13.5v and there is some melted plastic in that area. This could cause the battery to run down over time. Instead, you can do a voltage drop test first. But, I do have a volt meter installed and do note that here is a delay in the voltage getting back up into the 13 volt range. Car batteries have a resting voltage somewhere between 12.45 and 12.6 volts in most cases. Much like testing your car battery, a multimeter can be used to quickly tell whether your car’s charging system is adequately keeping the car battery at the proper charge, and operating the electrical system at the proper voltage as well.. Now it blows when I put the fuse in. The car will loose all charge after driving it for awhile. When a charging system fault appears, however, many car owners immediately assume a problem with the alternator, and replace it, hoping this will fix the problem. When the engine starts turning, the alternator is driven by a belt that converts mechanic power to electrical power. Its not broken/blown that I can see, but there is some bad scorching across that terminal. John, this means the alternator still not charging. The charging output of the alternator drops when diodes fail. The car always has to be jumped and even the jump does not last for long. Can the short be on another circuit affecting this too? In this picture, the right side terminal comes in from the alternator on the lower right tab/terminal. I'm not sure exactly if the alternator isn't putting out right away, or if the glow plugs are using all the available power.