Dead Battery after 3 days question
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
Dead Battery after 3 days question
I looked at all the past threads and just have a quick question
My glove box light was staying on, figured that out tonight.
Is that tiny bulb enough to kill a brand new battery in 3 days ? Or should I keep looking ? My Fluke meter will not work when I try to do an amp draw reading as I can never get the power to come back on in the car through the meter. I will grab another from work and try it this weekend
Thanks in advance
My glove box light was staying on, figured that out tonight.
Is that tiny bulb enough to kill a brand new battery in 3 days ? Or should I keep looking ? My Fluke meter will not work when I try to do an amp draw reading as I can never get the power to come back on in the car through the meter. I will grab another from work and try it this weekend
Thanks in advance
Melting Slicks
Joined: Sep 2008
Posts: 3,138
Likes: 802
From: Espanola New Mexico
That glovebox light will definitely discharge the battery, it's operation is only controlled by the switch. Your Fluke meter has a blown fuse, that is why it does not measure current or complete the circuit.
Melting Slicks
Joined: Apr 2019
Posts: 2,466
Likes: 700
From: Clark, NJ
For a parasitic draw test I use a battery disconnect switch on the negative terminal. Close the disconnect switch and then open the doors and close the door latches. Wait 20 minutes, the under hood light should go out. Using the fused 10A for the red lead and com for black connect each meter lead to a side of the battery disconnect switch, and open the switch. This helps avoid popping the meter fuse. Watch the draw on the meter and pull fuses. Try disconnecting the alternator.
There is another method of measuring voltage drop across each fuse some people prefer.
There is another method of measuring voltage drop across each fuse some people prefer.
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
Thanks for the reminder
I disconnected the light but i definitely want to make sure its nothing else
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
For a parasitic draw test I use a battery disconnect switch on the negative terminal. Close the disconnect switch and then open the doors and close the door latches. Wait 20 minutes, the under hood light should go out. Using the fused 10A for the red lead and com for black connect each meter lead to a side of the battery disconnect switch, and open the switch. This helps avoid popping the meter fuse. Watch the draw on the meter and pull fuses. Try disconnecting the alternator.
There is another method of measuring voltage drop across each fuse some people prefer.
There is another method of measuring voltage drop across each fuse some people prefer.
Thats a great idea !! thanks
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Drifting
Joined: Mar 2018
Posts: 1,365
Likes: 414
From: New Jersey
"I/P Compartment Lamp (Glovebox)
Voltage is supplied to the I/P Compartment lamp from CKT 640. CKT 640 receives battery voltage when the MONITORED LD Micro Relay #43 has closed its contact switch. The opening and closing of the MONITORED LD Micro Relay #43 is controlled by the BCM through CKT 1393. The BCM will ground CKT 1393 under normal operating conditions and energize the relay which in turn energizes CKT 640. Battery voltage is then supplied to the I/P Compartment Lamp and it becomes functional. The BCM will monitor CKT 640 at the BCM connector C2 terminal C4 for an inadvertent load. In the event that the I/P Compartment Lamp is inadvertently left ON, the BCM will remove the ground from CKT 1393 de-energizing the MONITORED LD Micro Relay #43 and removing battery voltage from CKT 640. This function is used to help prevent the battery from losing voltage over a period of time in the case of a load being left ON. The I/P Compartment Lamp is grounded by CKT 150 through Splice Pack #202 to G202."
Melting Slicks
Joined: Sep 2008
Posts: 3,138
Likes: 802
From: Espanola New Mexico
I stand corrected,if the BCM is functioning correctly it will turn off the glove box light. After my initial reply I verified this by leaving the glove box open and went back an hour latter and it was off, once I opened the door it came back on.
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
The.light is controlled by the BCM. Copied this from a previous posting here.
"I/P Compartment Lamp (Glovebox)
Voltage is supplied to the I/P Compartment lamp from CKT 640. CKT 640 receives battery voltage when the MONITORED LD Micro Relay #43 has closed its contact switch. The opening and closing of the MONITORED LD Micro Relay #43 is controlled by the BCM through CKT 1393. The BCM will ground CKT 1393 under normal operating conditions and energize the relay which in turn energizes CKT 640. Battery voltage is then supplied to the I/P Compartment Lamp and it becomes functional. The BCM will monitor CKT 640 at the BCM connector C2 terminal C4 for an inadvertent load. In the event that the I/P Compartment Lamp is inadvertently left ON, the BCM will remove the ground from CKT 1393 de-energizing the MONITORED LD Micro Relay #43 and removing battery voltage from CKT 640. This function is used to help prevent the battery from losing voltage over a period of time in the case of a load being left ON. The I/P Compartment Lamp is grounded by CKT 150 through Splice Pack #202 to G202."
"I/P Compartment Lamp (Glovebox)
Voltage is supplied to the I/P Compartment lamp from CKT 640. CKT 640 receives battery voltage when the MONITORED LD Micro Relay #43 has closed its contact switch. The opening and closing of the MONITORED LD Micro Relay #43 is controlled by the BCM through CKT 1393. The BCM will ground CKT 1393 under normal operating conditions and energize the relay which in turn energizes CKT 640. Battery voltage is then supplied to the I/P Compartment Lamp and it becomes functional. The BCM will monitor CKT 640 at the BCM connector C2 terminal C4 for an inadvertent load. In the event that the I/P Compartment Lamp is inadvertently left ON, the BCM will remove the ground from CKT 1393 de-energizing the MONITORED LD Micro Relay #43 and removing battery voltage from CKT 640. This function is used to help prevent the battery from losing voltage over a period of time in the case of a load being left ON. The I/P Compartment Lamp is grounded by CKT 150 through Splice Pack #202 to G202."
Drifting
Joined: Sep 2009
Posts: 1,862
Likes: 594
From: Prescott, Arizona
Read this thread in its entirety, especially post #15-
https://www.corvetteforum.com/forums...t-charger.html
https://www.corvetteforum.com/forums...t-charger.html
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
Well, did more research on the car today and in sleep mode its drawing 49 milliamps and I pulled every relay and fuse and that number never budged plus I also disconnected the alternator and no change
Is 49 ma enough to drain a fully charged brand new battery in 3 days ?
Is 49 ma enough to drain a fully charged brand new battery in 3 days ?
Melting Slicks
Joined: Sep 2008
Posts: 3,138
Likes: 802
From: Espanola New Mexico
Should be around 20-25 ma, and no even with 49 ma drain it should not drain the battery in 3 days. There is the possibility that the new battery may be bad, it is unusual but many here on the forum have experienced this problem.
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
The glove box light was not shutting off with the box closed so I disconnected that but the light did go off after a while when I tested it today
Still going to do more investigating at some point since I couldnt get the milliamps to drop at all but I never did check the headlight module but I would have expected a change when I pulled fuses and nothing
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
Ampper Side Post Battery Disconnect Switch, Battery Master Switch Isolator for Power Disconnect Cut Off (with Long Bolt) https://a.co/d/85wgyVP
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
Ok. So I left everything connected since 7pm last night and in 16 hours the battery voltage has dropped from 12.53 volts to 12.33 volts
I have no idea if that’s normal or not but at that rate we are looking at .3 - .4 volts a day until low voltage pulls it down quicker
I have no idea if that’s normal or not but at that rate we are looking at .3 - .4 volts a day until low voltage pulls it down quicker
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida