Updated with suggestions.
I posted this in my thread when asking about replacement battery suggestions. Someone said to check the alternator/generator too since I have an Etorque and it's a thing. (2021 Laramie 5.7 Etorque 86k+ mi)
Figure good for others to do if they are not volt meter savvy. And good to do after battery replacement
Night before
1. Set your dash display to the battery voltage display.
2. Turn off everything else: lights(toggle off position), blower for air ac/heat, radio, everything ECT.
Turn truck off let it sit couple minutes.
Next morning
3. Turn truck on ACC setting on your push button, NOT Run, and note battery voltage. It should be at a 12.xxV reading mine was 12.5V.
(depending on batter type 12.5-12.7V expected for good battery)
4. Now turn on the truck (Run motor on).
5. Turn on things that cause a heavy load all at once, Lights, Radio, Air Blower(ac/heat) etc.
6. The voltage should climb to a steady steady higher state with Mine was holding a 13.8V with occasional+/-0.1volts flux. Again my fluxes 13.7V sometimes 13.9V but mostly 13.8 even when driving a few niles when I picked up dinner when I did the test.
Normal ranges under load should be between 13.5V-14.1V
7. Don't forget to turn all that stuff off and your truck off
With those readings means the alternator is feeding the battery to keep it in it's 12.5-12.7V charge.
If you do have and know how to use a volt meter you can perform similar test.
When Parked for safety no driving!
1.Set volt meter to 20V test setting, usually counter clockwise setting.
2. Make sure everything is turn off and truck is off
3. Connect meter negative to battery negative terminal and positive to positive battery terminal. You should get a start 12.xxV reading.
4. Turn the truck on and put it under load by turning on your lights, radio, blower, etc
5. Retest the battery terminals and should show a steady 13.5-14.V reading.
Anything much lower and also much higher would be cause to take it to the dealer to check.
I posted this in my thread when asking about replacement battery suggestions. Someone said to check the alternator/generator too since I have an Etorque and it's a thing. (2021 Laramie 5.7 Etorque 86k+ mi)
Figure good for others to do if they are not volt meter savvy. And good to do after battery replacement
Night before
1. Set your dash display to the battery voltage display.
2. Turn off everything else: lights(toggle off position), blower for air ac/heat, radio, everything ECT.
Turn truck off let it sit couple minutes.
Next morning
3. Turn truck on ACC setting on your push button, NOT Run, and note battery voltage. It should be at a 12.xxV reading mine was 12.5V.
(depending on batter type 12.5-12.7V expected for good battery)
4. Now turn on the truck (Run motor on).
5. Turn on things that cause a heavy load all at once, Lights, Radio, Air Blower(ac/heat) etc.
6. The voltage should climb to a steady steady higher state with Mine was holding a 13.8V with occasional+/-0.1volts flux. Again my fluxes 13.7V sometimes 13.9V but mostly 13.8 even when driving a few niles when I picked up dinner when I did the test.
Normal ranges under load should be between 13.5V-14.1V
7. Don't forget to turn all that stuff off and your truck off
With those readings means the alternator is feeding the battery to keep it in it's 12.5-12.7V charge.
If you do have and know how to use a volt meter you can perform similar test.
When Parked for safety no driving!
1.Set volt meter to 20V test setting, usually counter clockwise setting.
2. Make sure everything is turn off and truck is off
3. Connect meter negative to battery negative terminal and positive to positive battery terminal. You should get a start 12.xxV reading.
4. Turn the truck on and put it under load by turning on your lights, radio, blower, etc
5. Retest the battery terminals and should show a steady 13.5-14.V reading.
Anything much lower and also much higher would be cause to take it to the dealer to check.
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