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Discussion Starter · #1 ·
I have a 2005 Street Rod. For a while now I have been having Battery drain problems. Getting worse recently to the point of the battery draining to 6 volts in 12 hours. There is a current drain of around half an amp. I have been isolating various circuits. Only when I pull the 15 amp ECM fuse does the problem go away (pin 31). My question is; is there a fault in the ECM itself causing the current draw or is it one of the components connencted to it. I could isolate each in turn but as they are scattered all over the bike, this could take a long time.
 

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I have a 2005 Street Rod. For a while now I have been having Battery drain problems. Getting worse recently to the point of the battery draining to 6 volts in 12 hours. There is a current drain of around half an amp. I have been isolating various circuits. Only when I pull the 15 amp ECM fuse does the problem go away (pin 31). My question is; is there a fault in the ECM itself causing the current draw or is it one of the components connencted to it. I could isolate each in turn but as they are scattered all over the bike, this could take a long time.
If the bike has an alarm fitted it's normal. Even with a new battery you would be lucky to get 2 weeks standing without the battery being flat. All the earlier models were like this, they need to be kept on a battery tender. As the battery gets tired the period of time will get less and less.
 

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Could be the diode in the voltage regulator if you have unplugged all the obvious drains ,yet the draw persists. Try unplugging it and retest draw.
Ron
 

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I have a 2005 Street Rod. For a while now I have been having Battery drain problems. Getting worse recently to the point of the battery draining to 6 volts in 12 hours. There is a current drain of around half an amp. I have been isolating various circuits. Only when I pull the 15 amp ECM fuse does the problem go away (pin 31). My question is; is there a fault in the ECM itself causing the current draw or is it one of the components connencted to it. I could isolate each in turn but as they are scattered all over the bike, this could take a long time.
streetrod ONLY made 2006-07
 

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Discussion Starter · #5 ·
This bike was purchased here in April 2005. The battery is new. I have completely removed the regulator and still get the drain. Yes I have always had a slow drain over a couple of weeks but this is a new problem, even the trickle charger can't cope. As I understand it, there is always a few milliamp draw from the ECM and TSSM but I am talking about 0.5 amps, enough to drain the battery below 12 volts in 2 hours and down to 6 volts in 12 hours.
 

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doesnt matter when you purchased its either an 07 or 06 if an r modell
anyway
have you had the battery tested for life percentage left ? I dont mean test the full charge voltage but what is left in the life of the cells.
is it decharging while the engine is running also ??
 

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Discussion Starter · #7 ·
It is a new battery which I bought because I originally thought that that was the problem. Both the new and the old one hold their charge provided I pull the ECM fuse. Charge also holds when engine is running. The problem is that there should not be a current drain of half an amp with the ignition off.
 

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If you have any after market electrical devices attached I would remove them and see what happens.
 

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The TSSM has a backup battery for the siren which is getting charged by the starter battery. It can be replaced. You could disconnect the TSSM and check if the starter battery issue is solved.
 

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Discussion Starter · #11 ·
Disconnected the TSSM, no change. Is one of the sensors connected to the ECM prone to shorting? Or injectors and coils, all of which have outputs from the ECM.
 

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Disconnected the TSSM, no change. Is one of the sensors connected to the ECM prone to shorting? Or injectors and coils, all of which have outputs from the ECM.
The following is the normal current draw for each item:
Regulator: 0.5 mA (0.0005 A)
TSSM (armed): 3.0 mA (0.003 A)
TSSM (disarmed): 0.5 mA (0.0005 A)
ECM: 1.0 mA (0.001 A)​
All the ECM controlled components are triggered on by transistor sinks to ground. IOW, the ECM has computer controlled circuits that short to ground when a component (injector, spark event, etc.) is switched on. So the actual current draw by the device is not supplied by the ECM fuse. Most of these receive power from the SYSTEM relay and this power is only present when the ignition is on and the RUN/STOP switch is set to RUN. I haven't heard of an ECM fault that would lead to excessive current draw with the ignition off.

Have you checked the blue with gray stripe wire (fed by ECM fuse) for shorts?

Is the check engine light on? (Do you have any DTCs?).
 

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Discussion Starter · #13 ·
Thanks for the info. No DTCs. Haven't had chance to check the wire yet. Currently running with an isolation switch to the contant power pin, which has stopped all power drain so the problem isn't so pressing but will have to get to the bottom of it though.
 

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Thanks for the info. No DTCs. Haven't had chance to check the wire yet. Currently running with an isolation switch to the contant power pin, which has stopped all power drain so the problem isn't so pressing but will have to get to the bottom of it though.
That wire makes a loop basically fused from battery to pin 31 for constant power to ECM. It also connects to the system relay. Have you pulled the relay to check drop? Power to ECM should still continue to pin 31 with relay removed so I wonder if it's possible the relay is sucking power? Pin 31 should read battery voltage even with relay removed.
Ron
 
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