How to monitor alternator output?

[swild]

I have a Bluetooth OBD scanner, but it doesn't tell me anything about my alternator amperage. How would I go about finding out those live numbers?

 

[llm]

you could possibly use a DC current clamp multimeter. I got one of these to check parasitic draw

I use this:

https://www.lowes.com/pd/Kobalt-KBLT-400A-AC-DC-RMS-CLAMP-METER/5015218721

 

[Rednexus]

The only thing you'll get from the OBD2 scanner is the voltage. I'm not sure the rig is capable of estimating alternator amperage on its own. The only way I am aware of for measuring current full-time would be to install a shunt on the negative battery terminal, and then mount a display inside the rig somewhere. This would measure current in amps and watts. I have one on the battery for my camper. They are not very hard to wire, although you'd want a very high capacity shunt (several hundred amps) to avoid frying it when starting the engine.

 

[WTITW]

Yeah, shunt is the only way. They are cheap though. https://www.amazon.com/dp/B0DJ2P2XN5/?tag=ihco-20

 

[swild]

Yeah, shunt is the only way. They are cheap though. https://www.amazon.com/dp/B0DJ2P2XN5/?tag=ihco-20

Good to know, thanks!

 

[r2m]

When driving, as long as my OBDII app is showing between 14.6 VDC to 14.9 VDC, I'm not worried.