***BATTERY DRAINAGE, 2003 DISCO 2****

[GrkPatriot77]

Good evening. Making my first post ever on this site hope everyone is well. I'm the proud owner of a 2003 discovery he's seven. I purchased this vehicle in 2015 from the original owner. Vehicle only had 50000 miles pampered its entire life garage kept.

Fast forward to late 2020, I have spent nearly 4k on vehicle in maintenance , basic things, ware and tare, breaks, ball joints, oil pump,water pump, new radiator, complete hoses, belts, full tune up, wires, etc, brake line replacement to stainless, and some upgrades.

What bugs me the most is that I purchase a new battery thinking that battery in the vehicle was simply old because I had never changed it before and after about a week with the new battery it was completely dead. Not sure what the hell happened I thought I left the lights on overnight. so I went back to AutoZone and used my warranty to get a new battery again! Installed it, kadted another week,, Came back tk it one morning could not start the vehicle. I haven't had the time to find a really great electrical expert I live in New York, Staten Island.

Brought the car to a pretty good mechanic unfortunately he could not find where the drainage was happening from he said he checked every fuse while car in off position but came up with nada.

This is bugging the hell out of me. I use vehicle daily and have to jump it every second day or if I leave it parked more than 10 hours. Tbrougiut the day I use it start stop.often so there is never an issue. Its just annoying having to open the hood often to use a booster pack.

 

[jastutte]

i assume you have tested the alternator to eliminate that as a possible problem.

 

[GrkPatriot77]

Well yes the mechanics tell me that the alternator seems OK since it continually charges the battery I can start the Vehicle up until 24 hours after I turn it off.

 

[HIDave]

Have you placed a voltage meter on the battery while the truck is running and while it is off?

The voltage should be +/- 12 while running. After the truck is off wait about 10-15 minutes until the very dim light on the dash appears. This means that the truck is "asleep' for lack of a better word. The voltage should be low very low, like .5 or less. If it is not then come back to us. Better yet pull some codes from the truck and post those.

There are a whole host of other reasons why electrical issues may have occurred, from:
Dried up gaskets allowing water ingress to an engine short

Simply because the truck has low miles does not mean it may not have any issues.

 

[mlnnc]

A common cause of a parasitic drain if the truck originally had air springs in the rear that were replaced with coils, but the SLABS computer setting was not changed from air to coils. The computer runs the SLS pump from time to time trying to level the truck. Check whether or not your truck had air springs from the factory but now has coils in the rear.

Beyond that just google "parasitic drain." There are plenty of online resources about how to use a multimeter set to measure amps to track down a parasitic drain. It can be a tedious, time consuming process, but it's not difficult.