Is there a procedure to track down excessive parasitic battery draw on can bus models that don't have fuses to pull?

 

Year and model of your bike would be useful. Most CAN Bus systems have fuses.

 

Their gonna have fuses somewhere I'd think.
Power and ground distribution schematics and possibly circuit schematics maybe needed.
Sometimes these things are simple and sometimes not so simple.

Have you got a DVOM ? and a manual?
Ya already been asked about year and model.
Good Luck WP

 

My CAN bus bike has 3 fuses, the main fuse, 40A, A 10Amp fuse for most of the components and the last one 15Amp for the tender charging lead. So in reality my bike only has one fuse. Everything else on the bike is reliant on the BCM to control current flow and protect itself from over current situations which is powered direct after the 40Amp main fuse.

Wiring diagram here:- 94000402pdf_en_us - 2017 Wiring Diagrams | Harley-Davidson SIP - select Sportster. The first sheet is the battery supply.

First you need an Ammeter that you connect in circuit to see current draw then using the wiring diagram you can pull the connectors to disconnect each component in turn.

When the bike is switched off each one ought to be drawing around 1mA.

 

That's what I was afraid of. With fuses, it's simple to isolate each section in turn. With can bus, it's all connected up in one big system.
By pulling connectors, I guess you mean each individual wire - a real headache.

I did do a draw test, but I'm not sure I did it exactly right. But....using a meter, and checking daily, I lose about 0.04V per day, which seems excessive to me.
If I let the bike sit for a month, it would lose 1.2V and probably not start. That's why I started another thread about installing a battery shutoff switch.
Still thinking things over. I like my current Sportster, but things were a lot simpler with my last one - a 1997.

 

Not individual wire connector component. So you disconnect ECM, then BCM, then right hand hand control, etc. With each disconnection you should see the current draw drop by approximately 1mA.

 

OK, thanks.
Doesn't sound quite as horrible now.

 

Can't see a way to edit my post, but after a quick look and thinking about it a bit, if I disconnect (for example), the ECM,
there are 2 connectors on it - one has 18 wires, and the other has 14, so there's still a bit of tracking down to be done.

 

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First...

Tell us what the issue is so we know what to troubleshoot.

What makes you think there is a parasitic draw?
It is not a common issue.

Before you start disconnecting stuff, first determine if you actually have a parasitic draw.

Forget about voltage, parasitic draw is measured in milliamps.

Disconnect the negative battery cable.

Set the meter to milliamps.

Touch one probe to the negative battery post, touch the other probe to the disconnected negative battery cable terminal.

Measure the milliamps, what does it read?