Battery Drain Test
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Battery Drain Test
I followed Bill Curlee's method of testing for amp draw.
The Meter fluctuates from .027 to .030 Amps , after 10 minutes of waiting.
Is this acceptable range?
The Meter fluctuates from .027 to .030 Amps , after 10 minutes of waiting.
Is this acceptable range?
Last edited by cam99; Oct 20, 2008 at 03:45 PM.
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Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Mine sat steady at one reading once it went to sleep. The lower the reading the better. .027 wouldnt be to bad but the fact that its cycling causes me concern. Something is trying to power up or down and it cant.
Check the following areas. Heres an extract from my current checking post:
C5's that drain batteries in days or a week have an excessive battery current draw issue. Here are a few places that have proven to be a cause of excessive battery current draw:
Drivers or Passengers seat control multifunction switch. The return spring in the switch gets weak or damaged and the seat sticks in a movement position. The motors are thermally protected by a "circuit breaker" in the passengers foot well and will continuously set and trip until the battery goes dead.
Drivers LUMBAR motor. Same as above!
Interior lights, dash lights, or other interior lights.
Head light motor control module. The module can short inside and draw current even though the lights are down and secure. If you feel the module and its HOT, its bad.
Alternator. The diodes can and do go bad. If hey go bad, the field windings will always be powered and draw current. If you suspect that the alternator is drawing current, remove the field terminal wire from the back of the alternator and insert the AMP Meter in SERIES with the circuit (between the red wire and alternator field terminal). The current draw should be ZERO. If you have current draw, one or more diodes are bad in the alternator. The last alternator that I checked this way was drawing 5 amps.
Bose Amplifier. Theres an amp under the dash on the drivers side dash. The relay for that amp sometimes sticks and the amp remains on even though the car is OFF.
Cell phones, radar detectors, wide band controllers ect... can get left plugged in.
NOTE! If you open the door, or trunk or even remove and then replace a fuse for troubleshooting, it will wake the car up and you will need to wait for it to enter the SLEEP mode again to read the current draw.
If you remove a BCM fuse, it will negate the test because the BCM is controlling the current draw.
Hope this helps figure out the reasons for premature battery failure.
Bill Curlee
Check the following areas. Heres an extract from my current checking post:
C5's that drain batteries in days or a week have an excessive battery current draw issue. Here are a few places that have proven to be a cause of excessive battery current draw:
Drivers or Passengers seat control multifunction switch. The return spring in the switch gets weak or damaged and the seat sticks in a movement position. The motors are thermally protected by a "circuit breaker" in the passengers foot well and will continuously set and trip until the battery goes dead.
Drivers LUMBAR motor. Same as above!
Interior lights, dash lights, or other interior lights.
Head light motor control module. The module can short inside and draw current even though the lights are down and secure. If you feel the module and its HOT, its bad.
Alternator. The diodes can and do go bad. If hey go bad, the field windings will always be powered and draw current. If you suspect that the alternator is drawing current, remove the field terminal wire from the back of the alternator and insert the AMP Meter in SERIES with the circuit (between the red wire and alternator field terminal). The current draw should be ZERO. If you have current draw, one or more diodes are bad in the alternator. The last alternator that I checked this way was drawing 5 amps.
Bose Amplifier. Theres an amp under the dash on the drivers side dash. The relay for that amp sometimes sticks and the amp remains on even though the car is OFF.
Cell phones, radar detectors, wide band controllers ect... can get left plugged in.
NOTE! If you open the door, or trunk or even remove and then replace a fuse for troubleshooting, it will wake the car up and you will need to wait for it to enter the SLEEP mode again to read the current draw.
If you remove a BCM fuse, it will negate the test because the BCM is controlling the current draw.
Hope this helps figure out the reasons for premature battery failure.
Bill Curlee
