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GMC Battery Questions

Is your battery going dead and need to know why? Need to know how long a GMC battery will last?

The complexity of the electrical system on GMC vehicles makes diagnosing battery problems difficult at times. The best way to know if a vehicle’s electrical problems are related to the battery is to obtain answers and guidance from Experts.

Read below where Experts have answered questions relating to the battery in a GMC.

What can cause a battery in a GMC Envoy to go dead?

If the battery is an old one, it may have become weak, which would explain why it suddenly died. Another reason could be that the battery has shorted. There could also be a problem with the charging system. Have the battery and the charging system checked to find the cause. If the battery and charging system check out okay, have the battery terminals and clips cleaned to allow for proper contact.

If a battery in a 2002 GMC Envoy SLT drains overnight, what could be wrong?

Case Details: The charging system and fuses have been checked and no defects have been found.

The problem could be that of ‘Parasitic Drain’ where some component is drawing power when the vehicle is switched off leading to the battery draining. To check the cause of the drain, a voltmeter or 12 volt test light will be required. Disconnect the negative terminal of the battery and connect the test light or voltmeter positive wire to the disconnected negative battery cable and the negative wire to the negative battery terminal. Turn off everything and if there is a hood light, remove the bulb. If the test light is out or the voltmeter is showing current, something is drawing power from the battery. Unhook the small wires at the alternator and if the light goes out or the voltage drops, there is a short in the alternator. If the light remains on or the voltmeter shows a draw, then the problem is elsewhere. Start pulling the fuse one at a time and when the light goes off or dims significantly or the voltmeter reading drops, that is the circuit where the problem is. The wiring and component will need to be checked. If the door has to be kept open to remove the fuses, push in the door switch button to turn off the light before doing the test. If none of the fuse checks produce a result, then it is likely that the drain is from an unfused circuit like a light switch.

What could cause a 1992 GMC Sierra with a new alternator and battery to over charge?

There are many reasons why this could be happening but the most common one is an issue with the alternator itself. The alternator has an internal voltage regulator which can fail and cause the GMC battery to overcharge. To check if this is the case the alternator will need to be tested with the correct electrical test equipment. Many auto parts stores will test he alternator and battery free of charge.

What could cause a 2004 GMC Blazer that has a key stuck in the ignition, to not start even with a new battery?

The most common cause for this type of issue is a defective ignition switch which is not providing the correct power output resulting in this kind of problem. Another common cause is a loose battery connection. Check to see if the connections are tight and the terminals are clean and corrosion free. If neither of these is the cause, a diagnostic scan can reveal where the problem is.

A 2005 GMC envoy has 12 volts with the battery cables disconnected but only 5 volts with the cables connected, what is the reason for this?

This most likely reason for this is that the GMC battery is bad. This kind of voltage drop is not normal. Take the battery to an auto parts store and ask for a battery test to be done. Even a new battery can go bad without warning.

The GMC battery is a critical component of a GMC vehicle’s electrical system. Defects and weak batteries can affect performance, cause starting problems and even leave the driver stranded. When dealing with battery issues it is best if the vehicle owner is aware of the possible causes of the problem and the solutions available. This will allow for the right repair decisions to be made. The answers and opinions of Experts can provide the owner with the information required to make the right choices.
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