Mazda Repair Questions? Ask Mechanics for Answers ASAP
Hello, my name is Bobby. Thank you for the question. It sounds like you either have a bad battery cable connection or the battery is failing internally. If it has an internal short then it can act fine at times and when being tested but as it heats up when you drive it can fail or the alternator may stop charging. Most of the time this occurs because of the battery cable though.
If you have a voltage meter I can run you through this. If not then it will be hard to tell.
No, you can leave it hooked up. With the engine running and the meter set to DC volts put one lead on the positive battery post without touching the cable end, and the other on the cable end without touching the post. Do this on each post separately. If you get a reading higher than .2 volts then the cable end is bad. If not then it should be fine. Then test from one end of the positive cable to the other end at the large wire at the alternator. Any more than .2 volts than that wires is the issue.
Sounds good. Let me know if you need more help.