VL Ammeter Wiring

[Peter Cooke]

Hi folks,
I’ve been reading as much as I can find on the forum regarding the VL amp gauge wiring issues, specifically the difference between the earlier, Weston, and later, Delco, gauges. I’m going to need to know eventually so decided to investigate.
I’m certainly no electrical expert so could be way off but I think I’ve got it figured out. Take a look at the attached pic and provide comment please.

Also attached is the wiring diagram that came with my loom. It shows power into the ammeter, from #7 via the dash lamp, at the left hand terminal and then straight to ground. I believe the ground should be on the right hand terminal.

If I have got it correct then the one thing I can’t figure out is how the ammeter still works when the light switch is ‘Off’ given that the ammeter gets its power from connection #7 which needs the light switch ‘On’ to be live.

All feedback greatly appreciated!


VL Ammeter Wiring.jpg
VL Wiring.jpg

[Scoot48]

Hello Peter, The yellow battery + wire goes to the right (looking from the top) ammeter terminal, the left amp terminal is grounded and also connects to the dash light. The hot side of the dash light comes from the light switch terminal that also feeds to tail light. There's a good diagram in the Rider's Handbook and Steve Slocomb's excellent book.

As an improvement to the grounding, HD added a ground wire from the dash ground to the frame-mounted timer cable clip screw, to avoid grounding path through the steering neck bearing. Shop Dope on that one.

Good luck. VLs are great rides.

[Scoot48]

Ooops. The yellow battery wire is the negative battery cable. Edit check.

[Peter Cooke]

Hello Peter, The yellow battery + wire goes to the right (looking from the top) ammeter terminal, .

The factory wiring diagrams show the yellow lead as negative at the battery. Being positive might make more sense though...

[Guest]

The yellow ground wire from the battery goes to the insulated ammeter terminal and the wire from the dash light goes to the grounded ammeter terminal. If the ammeter needle points toward the front, ground the right side terminal. If the needle points to the rear, ground the left side terminal. I can’t remember which one is the Delco or Weston. The one I got is from Poland and points to the front.

[Guest]

The ammeter is on the ground side of circuit . There are no hot wires going to it.

[Peter Cooke]

The one I got is from Poland and points to the front.

That's a Weston style then. I've changed my diagram to suit what I think you're saying. I'd appreciate you taking a look and commenting. If that's correct then the factory diagram I posted earlier shows the correct connection points for the Weston gauge but with the Delco gauge instead.

VL Ammeter Wiring1.jpg

[Peter Cooke]

The ammeter is on the ground side of circuit . There are no hot wires going to it.

Is this because it's positive into the lamp and then negative out of it to the ammeter?

[Guest]

Peter, I will try to send you a diagram but I’m not very good at posting them. You are getting closer. The best way I can explain it is the ammeter measures current while the current is on its way to ground. I know this whole ammeter issue is confusing. Well here comes the diagram, I hope.

[Guest]

I don’t know why my pictures get blurry when I post them. Let me try this.

[Peter Cooke]

Got them thanks. That makes a lot more sense. The golden rule appears to be yellow wire to the insulated post, ammeter/frame & lamp/ammeter wires to the other post, regardless of which type of ammeter it is.

"The best way I can explain it is the ammeter measures current while the current is on its way to ground." And this explains why the ammeter still works with the light switch off.


Thanks again dustydog.

Very much appreciated.