Battery keeps draining
Road Warrior
Joined: Sep 2006
Posts: 1,278
Likes: 2
From: Mission,BC.Canada
Always start with the simplest. Check the ground wire where it connects to the battery. They can become loose and on Sporties it is difficult to install a battery, while keeping the ground connection tight. Most mechanics miss this problem.
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,626
Likes: 6,443
From: Honah Lee
You need to put a milliamperage load meter on the - negative wire to the battery. With key off drain should be no more then 3.5 with FI and 0 for carb with no alarm. Note when you first hit key off the alarm will pull 16-25mil-amps for 30 seconds and then shut down to 3. That's the big spark you see and why you need a meter. If it is draining with key off I bet its the voltage regulator. A slightly bad diode in it will do it and it will still function. Takes special equipment to really check regulator other the output voltage.
Stellar HDF Member
Joined: Feb 2010
Posts: 3,400
Likes: 267
From: Southern California
If there is a short somewhere on the bike that is draining the battery there is a real easy way to diagnose this.
1.) Disconnect the Battery Ground Cable(s) from the Battery so that there are NO wires touching the Negative Terminal of the Battery.
2.) Make sure everything is turned off! (Very Important).
3.) Connect a Test Light between the Battery Negative Terminal and the disconnected Negative Battery Cable. Leave the Test Light connected for the rest of this test. If it becomes disconnected at any time, for any reason, restart the test from this step.
4.) Connect a Jumper wire between the Battery Negative Terminal and the disconnected Negative Battery Cable. (The jumper wire is now in parallel with the test light. The purpose of the jumper wire is to let any timer circuits in any of the electronic circuits to time out. If this is not done, the normal operation of various electronic timer circuits will have you falsely condemning one or more electronic boxes on the bike such as the TSS/TSSM, the ECU, etc.)
5.) After a minimum of 30 seconds remove the Jumper wire, but DO NOT remove the Test Light.
6.) If the Test Light is now glowing, even if it is glowing so faintly so that you have to cup your hands around it to see it, there is an excessive parasitic draw. No light means that there is NOT an excessive parasitic draw. Essentially you are using the Test Lamp as a cheap Ammeter. It takes a little bit more than about 35 milliamperes (0.035 Amperes) to make a Test Light filament glow. A current draw of less than 35 milliampers, such as the Voltage Regulator, Computer, Speedometer TSS/TSSM, etc normally consume is not enough to cause a problem.
7.) If the Test Lamp is on or is glowing even faintly, there is an excessive parasitic current draw. If this is the case more work is needed. If the Test Lamp is NOT on, you have a battery with an internal short . . . replace the battery and all will be well.
8.) If the Test light was on or was glowing even faintly there is an excessive parasite current draw. To find the offending item:
1.) Disconnect the Battery Ground Cable(s) from the Battery so that there are NO wires touching the Negative Terminal of the Battery.
2.) Make sure everything is turned off! (Very Important).
3.) Connect a Test Light between the Battery Negative Terminal and the disconnected Negative Battery Cable. Leave the Test Light connected for the rest of this test. If it becomes disconnected at any time, for any reason, restart the test from this step.
4.) Connect a Jumper wire between the Battery Negative Terminal and the disconnected Negative Battery Cable. (The jumper wire is now in parallel with the test light. The purpose of the jumper wire is to let any timer circuits in any of the electronic circuits to time out. If this is not done, the normal operation of various electronic timer circuits will have you falsely condemning one or more electronic boxes on the bike such as the TSS/TSSM, the ECU, etc.)
5.) After a minimum of 30 seconds remove the Jumper wire, but DO NOT remove the Test Light.
6.) If the Test Light is now glowing, even if it is glowing so faintly so that you have to cup your hands around it to see it, there is an excessive parasitic draw. No light means that there is NOT an excessive parasitic draw. Essentially you are using the Test Lamp as a cheap Ammeter. It takes a little bit more than about 35 milliamperes (0.035 Amperes) to make a Test Light filament glow. A current draw of less than 35 milliampers, such as the Voltage Regulator, Computer, Speedometer TSS/TSSM, etc normally consume is not enough to cause a problem.
7.) If the Test Lamp is on or is glowing even faintly, there is an excessive parasitic current draw. If this is the case more work is needed. If the Test Lamp is NOT on, you have a battery with an internal short . . . replace the battery and all will be well.
8.) If the Test light was on or was glowing even faintly there is an excessive parasite current draw. To find the offending item:
8A.) Pull each fuse one at a time until the Test light goes out to isolate the circuit causing the short. When the Test Light goes out replace all of the other Fuses to be sure that there is only one circuit causing the problem. Replace the Fuse on the offending circuit and then disconnect each item on that circuit until the Test Light goes out. When the light goes out you now know what part needs to be replaced and/or what wires need to be repaired.
8B.) If all the fuses are pulled and the test light is still illuminated (even faintly) then you have a shorted diode in the voltage regulator. Replace the Voltage Regulator.
Note: Loose wires, corroded connections, dirty connections, etc. will NOT cause a parasitic current draw. In fact, if anything, just the opposite is the case.
8B.) If all the fuses are pulled and the test light is still illuminated (even faintly) then you have a shorted diode in the voltage regulator. Replace the Voltage Regulator.
Novice
Joined: Feb 2007
Posts: 17
Likes: 0
From:
If there is a short somewhere on the bike that is draining the battery there is a real easy way to diagnose this.
1.) Disconnect the Battery Ground Cable(s) from the Battery so that there are NO wires touching the Negative Terminal of the Battery.
2.) Make sure everything is turned off! (Very Important).
3.) Connect a Test Light between the Battery Negative Terminal and the disconnected Negative Battery Cable. Leave the Test Light connected for the rest of this test. If it becomes disconnected at any time, for any reason, restart the test from this step.
4.) Connect a Jumper wire between the Battery Negative Terminal and the disconnected Negative Battery Cable. (The jumper wire is now in parallel with the test light. The purpose of the jumper wire is to let any timer circuits in any of the electronic circuits to time out. If this is not done, the normal operation of various electronic timer circuits will have you falsely condemning one or more electronic boxes on the bike such as the TSS/TSSM, the ECU, etc.)
5.) After a minimum of 30 seconds remove the Jumper wire, but DO NOT remove the Test Light.
6.) If the Test Light is now glowing, even if it is glowing so faintly so that you have to cup your hands around it to see it, there is an excessive parasitic draw. No light means that there is NOT an excessive parasitic draw. Essentially you are using the Test Lamp as a cheap Ammeter. It takes a little bit more than about 35 milliamperes (0.035 Amperes) to make a Test Light filament glow. A current draw of less than 35 milliampers, such as the Voltage Regulator, Computer, Speedometer TSS/TSSM, etc normally consume is not enough to cause a problem.
7.) If the Test Lamp is on or is glowing even faintly, there is an excessive parasitic current draw. If this is the case more work is needed. If the Test Lamp is NOT on, you have a battery with an internal short . . . replace the battery and all will be well.
8.) If the Test light was on or was glowing even faintly there is an excessive parasite current draw. To find the offending item:
1.) Disconnect the Battery Ground Cable(s) from the Battery so that there are NO wires touching the Negative Terminal of the Battery.
2.) Make sure everything is turned off! (Very Important).
3.) Connect a Test Light between the Battery Negative Terminal and the disconnected Negative Battery Cable. Leave the Test Light connected for the rest of this test. If it becomes disconnected at any time, for any reason, restart the test from this step.
4.) Connect a Jumper wire between the Battery Negative Terminal and the disconnected Negative Battery Cable. (The jumper wire is now in parallel with the test light. The purpose of the jumper wire is to let any timer circuits in any of the electronic circuits to time out. If this is not done, the normal operation of various electronic timer circuits will have you falsely condemning one or more electronic boxes on the bike such as the TSS/TSSM, the ECU, etc.)
5.) After a minimum of 30 seconds remove the Jumper wire, but DO NOT remove the Test Light.
6.) If the Test Light is now glowing, even if it is glowing so faintly so that you have to cup your hands around it to see it, there is an excessive parasitic draw. No light means that there is NOT an excessive parasitic draw. Essentially you are using the Test Lamp as a cheap Ammeter. It takes a little bit more than about 35 milliamperes (0.035 Amperes) to make a Test Light filament glow. A current draw of less than 35 milliampers, such as the Voltage Regulator, Computer, Speedometer TSS/TSSM, etc normally consume is not enough to cause a problem.
7.) If the Test Lamp is on or is glowing even faintly, there is an excessive parasitic current draw. If this is the case more work is needed. If the Test Lamp is NOT on, you have a battery with an internal short . . . replace the battery and all will be well.
8.) If the Test light was on or was glowing even faintly there is an excessive parasite current draw. To find the offending item:
8A.) Pull each fuse one at a time until the Test light goes out to isolate the circuit causing the short. When the Test Light goes out replace all of the other Fuses to be sure that there is only one circuit causing the problem. Replace the Fuse on the offending circuit and then disconnect each item on that circuit until the Test Light goes out. When the light goes out you now know what part needs to be replaced and/or what wires need to be repaired.
8B.) If all the fuses are pulled and the test light is still illuminated (even faintly) then you have a shorted diode in the voltage regulator. Replace the Voltage Regulator.
Note: Loose wires, corroded connections, dirty connections, etc. will NOT cause a parasitic current draw. In fact, if anything, just the opposite is the case.8B.) If all the fuses are pulled and the test light is still illuminated (even faintly) then you have a shorted diode in the voltage regulator. Replace the Voltage Regulator.
Seasoned HDF Member
Joined: Aug 2013
Posts: 35,824
Likes: 38,688
From: Post Falls, ID
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