Recently I bought an inverter to charge my 17" laptop when traveling in our '05 T&C Limited. The inverter handles 120 watts continuously, 150 peak. The charger for my laptop peaks at 85 watts. With a 20 amp fuse in this van, you'd think it would power this load effortlessly–but it doesn't. The inverter goes through the symptoms of having too little power (according to its manual).

I used the same setup in another car without issue, and I tried a different inverter with a smaller laptop–same problem. Out of all the outlets in the van, there is one that powers my setup almost without issue, and that's the one in the front, on the console, closest to the floor. I believe it's connected differently than the other outlets in that in doesn't go through the same fuse, but connects with the heated side mirrors to a larger fuse.

The voltage on the outlets are all roughly outputting 12.5. I've tried swapping the fuse to power the outlets through the battery or the ignition and I've tried this while driving and idling the engine, but there's no difference–all the outlets apparently output too little current (save for the one).

Is there something that can be done about this? I'd like to plug this setup in the back of the car instead of the front, and have the option to power the smaller laptop in another. Please advise.

 

Go under the hood and compare that 12.5 to what you read directly at the battery......More than a .3 difference is cause to look at the grounding system inside the car.

Since they arent Regulated.....You should expect to see an Identical reading at the outlet and at the battery.

 

Thanks for responding so quickly. The battery has a reading of 11.56v, with the outlets at 11.12v. (yesterday the voltage was higher as it had just been driven around)

What's the first step in checking the ground points?

 

After searching online for info on ground points I came across an article (that had nothing to do dc outlets) where the battery may have been the culprit of some electrical issues.

The battery in our van doesn't have any markings, stickers or anything on it–making me think it could be the original. I bought the car back in March, so I'm not sure if the previous owners have ever replaced it.

How can I check to see if it's in need of replacement?

 

The answer is in your previous post. 11.56v is very low. A fully charged new car battery would read well over 12.5v.

Your battery is definately suspect.

 

Shortly after posting about the battery I searched various ways to test it and went ahead and had a new one installed. However, the outlets still do their thing with the voltage varying roughly .45 volts lower than the battery... So I guess it's a ground issue still?