ECM Voltage Reading

Panther

Zoomer not a Boomer
Contributor
:
2016 MAZDA CX-5 GT AWD with TECH PKG / i-ActivSense
Hi All,

Several months back I'd gone on a long trip and when we got home my 2016 CX 5's battery was dead, and I'd left my UltraGage hooked up
but also the battery had been showing subtle signs of going out. So, I hooked up my UltraGage again yesterday and it was showing the
ECM Voltage from between 12.9 to 13.3 and I was wondering what are the normal ranges for this reading.

I do not, repeat do not know anything about electrical things so, please forgive me if I'm missing out on things.

I just want to make sure my charging system is working correctly as I don't drive that much anymore, less than 10K a year with a long
trip in there.

Thanks for your help and info !!!

Take Care,

Craig
 
Is that with the engine running or not? I'll check mine later.
 
Is that with the engine running or not? I'll check mine later.

Hi Chris,

Mine only comes on with the engine on , and it stays about 12.9 -13.1-2 when idling and lower rpm and then
up to 13.0-13-3 when running mid to upper revs.

Thanks for your help, I guess I just keep thinking that it should be higher closer to 14 but didn't know about the Mazda's,
again, I'm kind of clueless on these things so ;-)

Take Care,

Craig
 
Hi All,

Thought I'd check back in, I went and Bought a Multi-Meter , have always wanted one and
don't know why it took this long. Anyway, checked the battery at rest 12.8 Volts, then started
the Engine and it was running 13.5 at the Battery Posts and the UltraGage was reading 13.3

I think I'd seen where you can adjust the UG but it uses the Voltage in one of the shutdown modes
to sense when to turn off.

Take Care,

CK
 
The resting voltage 12.8 seems good. You may want to go to pepboys/auto zone for them to test battery. They can load test and tell you how much cranking amp is giving out from the battery. Sometimes a bad battery can still start a car months. And when the winter comes, its much harder to start.

Your measurement of running engine with 13.3-13.5 sounds good voltage from the alternator. I think good voltage from alternator is 13.x to 14.0 volts.
 
The resting voltage 12.8 seems good. You may want to go to pepboys/auto zone for them to test battery. They can load test and tell you how much cranking amp is giving out from the battery. Sometimes a bad battery can still start a car months. And when the winter comes, its much harder to start.

Your measurement of running engine with 13.3-13.5 sounds good voltage from the alternator. I think good voltage from alternator is 13.x to 14.0 volts.



Thanks Sachi, I've got a new battery and just wanted to find out the Charging Volts
with the Scan Gauge a buddy kept insisting that it was 14.0 or more. So now I know that's
not the case, maybe those Voltage ranges are more for American Cars ??? Plus, you can check
the cranking volts but I was doing it by myself but if it's 10 Volts are more while Cranking it's good to go.

Take Care,

CK
 
Thanks Chris My UltraGage has a check with the ignition On by using the Up Button and it'll
flash the Voltage for a few seconds but again just didn't know if it was accurate.

Take Care,

CK
 
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