What should battery voltage be on GM Truck?

What should battery voltage be on GM Truck?

It appears the needle fluctuates between 12 and 15 or volts. The battery gauges on most vehicles I have owned stays around 13 to 14 volts and doesn’t move much unless something that consumes a lot of power is turned on. Mine does this with nothing additional running on the truck other than the radio and a/c.

What should the voltage be on a GM alternator?

GM typically runs a fusible link wire between them for overload protection and they can go bad, mimicking a bad alternator. A voltage drop of .25 volts or less is Ok and the alternator is bad. A voltage drop of .5 volts or more means the wire is bad.

Why does the battery gauge go back to 12 volts?

When your gauge read ~12volts and a new battery it went back to 15 volts, the old battery was overloading the alternator with an internal short. At one time I had a battery short bring it down to 9 volts and the computer went nuts. The engine back fired I just made it to a battery shop.

Why does the Volt gauge fluctuate while the engine is running?

If you have voltage fluctuations while the engine is running it is an indicator of a problem with the charging circuit, or a major short. The battery condition is not related to the voltage guage unless it is really shot, and we can see this is not the case. Either you have something kicking in and causing a major draw, or a bad voltage regulator.

It appears the needle fluctuates between 12 and 15 or volts. The battery gauges on most vehicles I have owned stays around 13 to 14 volts and doesn’t move much unless something that consumes a lot of power is turned on. Mine does this with nothing additional running on the truck other than the radio and a/c.

What are the symptoms of a bad alternator in a GMC Sierra?

Here are the most common symptoms of a bad alternator in a GMC Sierra: The battery light is designed to tell you that there is not enough voltage to properly charge the battery, or that the battery itself is not holding the proper voltage. In rare occasions the service engine soon light may light up.

What causes the idle voltage on a GMC Yukon?

Items that affect the vehicle’s electrical system current and voltage at idle are the number of electrical loads being used, including add-on accessories, and extended idle times.

When is dimming lights at idle considered normal?

When the vehicle speed is above approximately 24 km/h (15 mph), the engine/generator RPM is high enough and the generator current (amperage) output is sufficient to supply the current (amperage) requirements of the vehicle as originally equipped and recharge the battery. Dimming lights at idle may be considered normal for two reasons: 1.