I have the OE battery in my 2004 LT and I think it's getting tired. I suppose it's a Gel model. Somebody gave me a BMW branded maintainer spec'd for the Gel, and I have used it fairly often. A couple of times I have let the thing run down when I forgot to switch the key to lock ( My sirius and gps get power in the R position). I have noticed that the beast starts a little slowly some mornings when I have not plugged in the maintainer. And when idling for a long stop light, the idle speed will pick up a bit, which indicates a low voltage. So I bought one of these units, hooked it to the map light wires, and stuck the remote LED into the back of the map light itself. It shines through nicely, and no need to drill a hole. The light will remind me to lock the lock from now on! Even if I forget for a while, the light pulls only 20 mils.
LED Heads Up Voltage Monitor.
The specs on the Custom Dynamics site are wrong.
They are, per Signal Dynamics:
Steady Green - Above 12.9
Steady Amber - Above 12.6
Steady Red - Above 12.1
Flashing Red - Below 12 VDC – During this condition, if the engine is running, do not shut down until service can be provided. Restart of engine is unlikely. Reduce electrical load.
This morning, the light was red when I put the key to R. When I put it to On, it flashed red. I thumbed the starter, and she turned over slowly and started. Then the light turned green. When I got to work, I stopped in my spot, and let it idle. It quickly went to amber, then to red as I sat there.
So I think I'll pull the battery out tonight, and put it on a 2 amp automatic charger and let it fill up, and see if it works any better. I wonder if I should just order a battery, or if the charging system is working properly. Thoughts anyone?