I have a Nissan Almera 1999 N15 GA16DE, for some reason it drains the battery occasionally when the car is off and parked. If I leave the battery cables connected, it takes about a week for it to drain the battery.. Also the dashboard gauges show whatever, sometimes the speedometer and RPM gauge show 0 even though im driving.. Sometimes they work normal though.. And when the car is parked and turned off, the fuel gauge is usually at MAX even though it should be at 0, so there is some electrical problem going on..
Could it be faulty ECM? Bad grounding? I ordered OBD1 adapter so maybe it will help me locate the problem.. Also I removed the 3 connectors behind dashboard and put them back in, I dont think they are causing the issue.. And there are couple of blown light bulbs in the dashboard, I couldnt find similar bulbs from local stores but I dont think they are causing this issue either..
You might have a parasitic electrical drain. That will cause unusual readings from your gauges. The other two possibilities could cause them too. Unless you can troubleshoot the electrical system, take it to a shop for diagnosis.
edit: I found a fuse to my multimeter and I connected the battery in series with the terminal.. The car pulls 0.02-0.03A when parked which is probably normal.. However, it still drains the battery for some reason.. I think it just decides at some point to draw more power and then it has no power to turn the engine on.. I will keep the cable connected and keep a log of battery capacity over days and see when it drains it..
