alternator ???

[vt_maverick]

Home built by LiquidVX. I need to do a build thread but I've been procrastinating since I'm not satisfied with the fit and finish just yet. I calculated its max draw at only 46W so I'm wondering if maybe the problem is a dying alternator.

[etlsport]

Have you had the battery tested? An internal short within your battery would drop your voltage to around 10V quickly so your pc may not power up but the vx would still start off of the 5 good cells. AGM batteries use very thin glassmat separators that are prone to internal shorts from very low voltage, undercharge and physical abuse. (I am still a huge fan of agm type batteries and die hard platinum batteries but they are not without flaws)

As far as your alternator... has it been tested? A clamp on type ammeter would tell you how its doing quickly. Keep in mind that a typical HO alternator can only provide 75A of current at idle and will not start to produce high current until 1200rpm or higher. I had a 150A alternator I believe it was alterstart brand. It performed well but my battery light was always on for some reason I never figured out and after a couple years the voltage regulator quit, so it was producing 18+volts. When that happened the trans locked in 3rd gear and the engine went into safe mode. Only way to get it home was to remove the serpentine belt and drive directly from the battery. By time I figured out what happened I had fried my abs module, rear camera and most of the lights in the car.

Upgrading the cabling in the car will help by reducing resistance and voltage drop but if the alternator or battery has a problem it wont help

I cant remember how we hooked everything up but the first place I would look is to pull the fuse for the pc and see if it is drawing excessive current while it is off. If tyat is the case you will need to find a way to stop it or get a larger battery or maybe a second battery to handle the extra load when the car is off.