Voltage question

Yeah, Insulated(hot) side should not see a voltage drop >.4 and the un-insulated side(negative) should not see a voltage drop > .2
:redface:Dummy me didn't remove the circuit board form inside the cell phone lighter adapter which contains a resistor that obviously reduces voltage for charging a cell phone so I would never see 12v, only 6v which would power/charge the cell phone. Sorry for the senior moment. Will also be able to flip the fluke over to AC and see if the rectifier diode leaks are over spec when I get this adapter redone.

Yeah, most cell phones actually charge at 5-6 Volts (USB standard voltage) so that would explain your earlier results!
 
Sorry for opening an old thread. I felt it was appropriate to post it here.

Since operating charging voltage is 13.7v - 14.0v at idle, my scangauge II is reading 13.5v- 13.6v as of late at idle and under loading.

Is it time to replace my battery?

BTW, the scangauge II is an awesome gauge.
 
Sorry for opening an old thread. I felt it was appropriate to post it here.

Since operating charging voltage is 13.7v - 14.0v at idle, my scangauge II is reading 13.5v- 13.6v as of late at idle and under loading.

Is it time to replace my battery?

BTW, the scangauge II is an awesome gauge.

No, that sounds normal to me.
 
Sorry for opening an old thread. I felt it was appropriate to post it here.

Since operating charging voltage is 13.7v - 14.0v at idle, my scangauge II is reading 13.5v- 13.6v as of late at idle and under loading.

Is it time to replace my battery?

BTW, the scangauge II is an awesome gauge.

Trick question, huh? Charging voltage has little to do with battery health, except that poor charging performance will likely kill a battery eventually.

If you want to check battery health, charge it up and find someone to do a load test. If you want to check your charging system, go here:

http://www.teamtoyota4x4.org/archivio/1996%20to%202002%20Toyota%204Runner%20Repair%20and%20Wiring%20Manuals/techinfo.toyota.com/ileaf/02toyrm/02toypdf/02rmsour/2002/024runne/ch5vzfe/chasy/ovi.pdf

Idle voltages are not that important. 2000 RPM values are what you want to look at. Always worth cleaning terminals and grounds and inspecting cables.
 
Last edited:
That voltage on the scangauge display is voltage read at the ECU or ignition module. It will be different than the reading at the battery posts. I have a volt meter in my cig lighter to watch the charging and system voltage.


Sent from my iPhone using Tapatalk
 
Sorry for opening an old thread. I felt it was appropriate to post it here.

Since operating charging voltage is 13.7v - 14.0v at idle, my scangauge II is reading 13.5v- 13.6v as of late at idle and under loading.

Is it time to replace my battery?

BTW, the scangauge II is an awesome gauge.
Charging voltage is regulated by temperature. On a cold morning, you could see 14.3 or maybe higher, on a hot day 13.5.
 
Charging voltage is regulated by temperature. On a cold morning, you could see 14.3 or maybe higher, on a hot day 13.5.

Thanks, you're right! I see 14.0 in the morning going to work and 13.5-13.7 in the day going home in 80 degree weather.
 

Members online

Forum statistics

Threads
278,305
Messages
3,554,044
Members
248,016
Latest member
Advally Service

Trending content

Back
Top