Current drain.
Thread Starter
TECH Apprentice
Joined: Jan 2004
Posts: 315
Likes: 2
Current drain. I have been having problems with my battery being drained lately. I checked the amps being drawn while the car is off. It reads 90 miliamps. The stock drain should be 30-40 miliamps, or so I thought. Of the 90 being drained, 20 is coming from my aftermarket amps. Any ideas why the drain from the amps? Also, the other 60-70 being drained, I traced to the courtesy light fuse(It drops to between 10 and 0 miliamps when disconnected. Is this fuse the only one that is hooked up to something that stays on with the car off?
Also, I checked a buddies car and his was also 90 and his amp was also draining 20. Is 90 normal for our cars?
Also, I checked a buddies car and his was also 90 and his amp was also draining 20. Is 90 normal for our cars?
I have a thread open dealing with the same problem. Normal drain should definitely be 30-40 mA. My car was pulling about 300-400 mA and would go dead in about 2 days. Look in the owners manual to see exactly what is affected by the courtesy light fuse and then go from there.
TECH Enthusiast
Joined: Apr 2003
Posts: 561
Likes: 0
From: silver Spring MD
Originally Posted by Rare96WS6
I have been having problems with my battery being drained lately. I checked the amps being drawn while the car is off. It reads 90 miliamps. The stock drain should be 30-40 miliamps, or so I thought. Of the 90 being drained, 20 is coming from my aftermarket amps. Any ideas why the drain from the amps? Also, the other 60-70 being drained, I traced to the courtesy light fuse(It drops to between 10 and 0 miliamps when disconnected. Is this fuse the only one that is hooked up to something that stays on with the car off?
Also, I checked a buddies car and his was also 90 and his amp was also draining 20. Is 90 normal for our cars?
Also, I checked a buddies car and his was also 90 and his amp was also draining 20. Is 90 normal for our cars?
Wait a minute - when the car is off, the AMP should not be taking any current unless it has a memory or something else that needs to be powered up. Do you have an Alarm system in the car? That could draw some current.
The total system is wired thru fuses, so you can remove fuses and see which is causing the drain. Also be aware that some times, invisible minerals collect on top of your or side and will conduct current to the ground pole. Wash the battery with baking soda. How old is the battery? Keep in mind that 90ma = 11 hours/1 amp
Bill
As stated, the amps shouldn't draw anything when off.
The only things drawing current should be the alarm (if present), clock, and computer. 90mA does not seem high, 30-40mA seems low.
Even at 90mA, battery should still start the car days afterwards. Most batteries have cold cranking amp ratings over 500 amps.
Have you checked the current draw out of the battery through the positive and negative terminals? You problem could be befiore the fuse block. Battery cables, alternator, starter, etc.
Measure current flow directly off the battery through ammeter on both + and - sides. I think you problem is on the engine side of the firewall.
Post up those numbers when you have them.
The only things drawing current should be the alarm (if present), clock, and computer. 90mA does not seem high, 30-40mA seems low.
Even at 90mA, battery should still start the car days afterwards. Most batteries have cold cranking amp ratings over 500 amps.
Have you checked the current draw out of the battery through the positive and negative terminals? You problem could be befiore the fuse block. Battery cables, alternator, starter, etc.
Measure current flow directly off the battery through ammeter on both + and - sides. I think you problem is on the engine side of the firewall.
Post up those numbers when you have them.
Thread Starter
TECH Apprentice
Joined: Jan 2004
Posts: 315
Likes: 2
Strange, both cars pull 20 miliamps from the amplifiers when off. I know that the rest of the drain is from the courtesy light fuse. Weird that both cars read 90 when off, both cars also read 70 from the courtesy light fuse. My car does not have an alarm. My battery is 2 years old, and it is clean. It is a Hawker Genesis. My buddies car sits for weeks at a time and does not drain enought so that it won't start, so appartently 90 is not too much of a drain. Mine will not sit for very long without draining. I know it is the battery, since it will drain when not in the car, just sitting. I just think it is weird that both 1996 TA's read the same 90 miliamps when the cars are off. I saw the other posts on this topic, that is why I wrote this one. I wonder if any of you guys could check next time you are working on your cars to see what the drain is. I am currious to know if 90 is in the normal range, or if I should definitely seek to be in the 30-40 range.
Thread Starter
TECH Apprentice
Joined: Jan 2004
Posts: 315
Likes: 2
I checked the alternator voltage with the key in the on possition and then running. It was at 12.5 volts off, 14.7 running. The battery is getting a good charge. If the 90 miliamps is a normal figure for our cars, then it is the battery. It is being charged good while the car is running, and 90 is not too much of a drain, so I bet I will find that if I leave it out of the vehicle for a few days, it still looses power.
