Low Voltage Alarm

have you checked all of your battery and alternator connections? If that gets wet it could be a slight short not a dead short but just one that is for a second or 2 and that may cause it to read ) output from the alternator.

 

Any problems starting the truck??

I would check the alternator and connections as it has a built in voltage regulator.

When it happens again, check the alternator output with a tester, truck running. It should be about 14.0 Volts. 13.5V is acceptable but weak.

It does have a little brain box too that contains a shutdown relay. Where it is on your truck, I don't know, but it should be close to the fuse panel. It could have a bad connection or be on the blink.

All else fails you can call it your heavy rain gauge. Just kiddin.

 

One time my dash lights would go out when it rained.checked fuse, it was blown. replaced blew immed. found out there was part of a bare wire in back of tractor that was real close to the frame. it was not touching, but was so close that a drop of water running down the wire would be enough to make contact. since water conducts electricity, somewhere on your truck, most likely outside there may be a wire making contact only thru the water.

 

The LVD (low voltage disconnect) is either in the panel behind the passenger seat or under the center dash console. It gets its power feed from the 4 large terminal bars in the fuse block in front of the pass seat. The wiring runs down the inside of the cab and along the threshold plate (or under it) to the LVD if its in the back. Look for a water leak somewhere in that area would be the first place to start

 

POS front windshield design...and cheap sealant.

 

Is there a voltage regulator somewhere between the batteries and the alternator?