qnz
08-21-2012, 05:58 PM
I have a volt gauge in the car and it reads my voltage is normal when The car starts up (14.0-13.7v) but after driving for an hour or so, it will be reading at 13.0v. I test with a multimeter at the different sources and my multimeter confirms what the volt gauge reads.
However at the battery, it still reads ~13.8. When I measure at the fuse box and at the constant power at the radio, it reads the same ~13.7.
Why would the reading at the accessory power (where my volt gauge is tapped) read different from the main power? Aren't they coming from the same power source? What would account for the voltage drop while driving also. I changed the alternator thinking that was it but it didn't fix the problem
However at the battery, it still reads ~13.8. When I measure at the fuse box and at the constant power at the radio, it reads the same ~13.7.
Why would the reading at the accessory power (where my volt gauge is tapped) read different from the main power? Aren't they coming from the same power source? What would account for the voltage drop while driving also. I changed the alternator thinking that was it but it didn't fix the problem