BCM draws 270 mA from battery, normal?
canatto
11-05-2005, 11:02 AM
The battery in my 2000 GLS has just died so I put in a new one. Out of curiosity I took a current draw reading at the time of installation, and to my surprise it's 270 mA when nothing is on! My other car, a 1997 Ford Contour, draws only 20 mA, so 270 mA seems to me more or less a concern of battery being drained. By pulling the fuses one at a time I narrowed it down to the BCM - Body Control Module. Will call GM next Monday to see what they have to say. Wondering if a current draw of this much is normal. Would appreciate any comments.
GMMerlin
11-05-2005, 11:55 AM
Sounds excessive.
Did you allow the vehicle to power down before you checked the parasitic load on the battery? Usually this takes about 10-15 minutes.
Note the battery reserve capacity.
- Divide the reserve capacity by 4.
- Compare this to the multimeter milliampere reading taken in the previous step.
- The parasitic current drain should not exceed this number.
- Example: If a battery has a reserve capacity of 100 minutes, the current drain should not exceed 25 mA.
Did you allow the vehicle to power down before you checked the parasitic load on the battery? Usually this takes about 10-15 minutes.
Note the battery reserve capacity.
- Divide the reserve capacity by 4.
- Compare this to the multimeter milliampere reading taken in the previous step.
- The parasitic current drain should not exceed this number.
- Example: If a battery has a reserve capacity of 100 minutes, the current drain should not exceed 25 mA.
BNaylor
11-05-2005, 01:47 PM
Sounds excessive.
Did you allow the vehicle to power down before you checked the parasitic load on the battery? Usually this takes about 10-15 minutes.
Note the battery reserve capacity.
- Divide the reserve capacity by 4.
- Compare this to the multimeter milliampere reading taken in the previous step.
- The parasitic current drain should not exceed this number.
- Example: If a battery has a reserve capacity of 100 minutes, the current drain should not exceed 25 mA.
Great responsive post K. If accurate definitely high. I agree. The 270 mA is just about 3/10th of an amp draw.
I thought a typical 'W" body BCM, of course depending on the model, has a draw in a range of appoximately 3.6 mA (normal) to 12.4 mA (max) for parasitic load? Correct me if I'm wrong. :dunno:
Did you allow the vehicle to power down before you checked the parasitic load on the battery? Usually this takes about 10-15 minutes.
Note the battery reserve capacity.
- Divide the reserve capacity by 4.
- Compare this to the multimeter milliampere reading taken in the previous step.
- The parasitic current drain should not exceed this number.
- Example: If a battery has a reserve capacity of 100 minutes, the current drain should not exceed 25 mA.
Great responsive post K. If accurate definitely high. I agree. The 270 mA is just about 3/10th of an amp draw.
I thought a typical 'W" body BCM, of course depending on the model, has a draw in a range of appoximately 3.6 mA (normal) to 12.4 mA (max) for parasitic load? Correct me if I'm wrong. :dunno:
maxwedge
11-05-2005, 02:52 PM
Shouldn't he be using a clamp on attachment to check the current draw to insure not keeping the modules "awake"? PS, Bnaylor, I see you are an NHRA member, back " when" I was an NHRA recolder holder with my 64 Belvedere 426 Ramcharger. mph 122.80, in A/SA.
BNaylor
11-05-2005, 03:16 PM
Shouldn't he be using a clamp on attachment to check the current draw to insure not keeping the modules "awake"? PS, Bnaylor, I see you are an NHRA member, back " when" I was an NHRA recolder holder with my 64 Belvedere 426 Ramcharger. mph 122.80, in A/SA.
Technically yes. He should use a Disconnect Tool (Kent-Moore J-38758 or similar) connected to the battery negative side.
Yeah, I still maintain NHRA membership for what it's worth. Our local track is IHRA. What year did you have your record? Back in '74 I raced a modded '70 Dodge Challenger R/T 440 Magnum in the Super Stock class. Those were the good ole days.
Technically yes. He should use a Disconnect Tool (Kent-Moore J-38758 or similar) connected to the battery negative side.
Yeah, I still maintain NHRA membership for what it's worth. Our local track is IHRA. What year did you have your record? Back in '74 I raced a modded '70 Dodge Challenger R/T 440 Magnum in the Super Stock class. Those were the good ole days.
maxwedge
11-05-2005, 04:18 PM
Technically yes. He should use a Disconnect Tool (Kent-Moore J-38758 or similar) connected to the battery negative side.
Yeah, I still maintain NHRA membership for what it's worth. Our local track is IHRA. What year did you have your record? Back in '74 I raced a modded '70 Dodge Challenger R/T 440 Magnum in the Super Stock class. Those were the good ole days.
Set it at a division meet 79 or 80 I think, at Englishtown. Purposely did not lower the et record or that would ahve been a new handicap in the eliminator, the stage 111 wedge was pretty strong, all steel car. Ran this combo from 72-88!!! Also ran in SS/BA with a crossram 426 Hemi and aluminum front end, was too tough to keep running and hard to hook at that time, no narrowed rears like today, 10.5 tires!! These cars are worth big bucks now. Sounds like SS/FA for you?
Yeah, I still maintain NHRA membership for what it's worth. Our local track is IHRA. What year did you have your record? Back in '74 I raced a modded '70 Dodge Challenger R/T 440 Magnum in the Super Stock class. Those were the good ole days.
Set it at a division meet 79 or 80 I think, at Englishtown. Purposely did not lower the et record or that would ahve been a new handicap in the eliminator, the stage 111 wedge was pretty strong, all steel car. Ran this combo from 72-88!!! Also ran in SS/BA with a crossram 426 Hemi and aluminum front end, was too tough to keep running and hard to hook at that time, no narrowed rears like today, 10.5 tires!! These cars are worth big bucks now. Sounds like SS/FA for you?
BNaylor
11-05-2005, 08:50 PM
Set it at a division meet 79 or 80 I think, at Englishtown. Purposely did not lower the et record or that would ahve been a new handicap in the eliminator, the stage 111 wedge was pretty strong, all steel car. Ran this combo from 72-88!!! Also ran in SS/BA with a crossram 426 Hemi and aluminum front end, was too tough to keep running and hard to hook at that time, no narrowed rears like today, 10.5 tires!! These cars are worth big bucks now. Sounds like SS/FA for you?
SS/FA? I wish. No not quite. Ran out of time and money. Got shipped off overseas in the service. Killed my drag racing days for a while. I recall my index was in the SS/LA class. She was a solid high 11 sec. performer. Lots of money into it for back in those days. I sold it and got a stock, cream puff '70 Chevelle SS 454 LS6/M22 for $999.00. Like an idiot sold it in 1980. I've heard of a LS6 going for up to $100K now.
Nowadays, just to keep things going and exciting I run ET/Bracket with my GTP and Vet. 250cc class with my Honda CR250 motocross bike. Never too old. Oh well. Live n learn. Nice chatting.
SS/FA? I wish. No not quite. Ran out of time and money. Got shipped off overseas in the service. Killed my drag racing days for a while. I recall my index was in the SS/LA class. She was a solid high 11 sec. performer. Lots of money into it for back in those days. I sold it and got a stock, cream puff '70 Chevelle SS 454 LS6/M22 for $999.00. Like an idiot sold it in 1980. I've heard of a LS6 going for up to $100K now.
Nowadays, just to keep things going and exciting I run ET/Bracket with my GTP and Vet. 250cc class with my Honda CR250 motocross bike. Never too old. Oh well. Live n learn. Nice chatting.
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