Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[gadgetgirl]

I'm starting on a small project to add CarPlay/Android Auto to my 2020 SR/F. I'm hoping to tap into the collective wisdom of folks that have wired accessories to their bikes.

I bought a Carpuride W502 little device that needs 12V/1A as far as I can tell (they aren't great at publishing coherent specs). It comes with a fused power cable with raw wire ends. I had a fused SAE pigtail from an old BatteryTender Jr. laying around, so I cut off the ring terminators and soldered the red and black wires to the Carpuride red and black wires. So, at this point, I had a power cable with two fuses on it (one 7.5A fuse on the pigtail red wire, and one marked "3" on the Carpuride segment). I figured double fusing shouldn't matter as long as they're both on the power line, not the ground.

I plugged it into the SR/F SAE accessory port and switched on the bike. The headlight and dash blinked off and on, error code 27 12V low power error came up, and the "3" fuse was blown. I replaced the fuse with a 15A fuse, the 7.5A fuse blew, error code 27.

So, now I'm at the troubleshooting stage.
1) am I dumb and double fusing has some problem? I can (and might) just cut off one or both of the fuses since fusing is really intended when wiring straight to a 12V battery, not the DC-DC converter like I'm trying to do. Right?
2) I can't guarantee that the Carpuride unit isn't defective. there's no obvious short that I can find, but maybe internally it's borked. I guess I should start probing everything with a multimeter
3) my SAE accessory port could be borked. this is the first time I've tried using it. The power side was still crammed with dielectric grease, but it looked clean overall. I did test it separately with a CTEK indicator pigtail (https://smartercharger.com/collections/accessories/products/ctek-comfort-indicator-pigtail) and the green light blinked, which I think means good.
4) I'm waiting for a USB Carpuride cable to arrive to try that out. That way I can just plug it into the storage bin USB port. This will probably work, but it's seems sort of dumb to go from DC-DC 12V -> 5V -> 12V with who knows how many amps.

I'm mostly looking for reassurance that this isn't a fool's errand, and that I'm not making some glaring mistake. The links to stuff like this on the unofficial Zero wiki are dead links, so I'll just persevere and figure it out:

[TheRan]

That's a decent chunk of power to be blowing a 7.5A fuse, definitely something abnormal like a short and not a fault on your part. What I would do is get rid of the second fuse holder so you just have the one with the 15A fuse in and then connect just the pigtail without it plugged into the device, if the fuse blows then you know the short is in that part of the cable. Of course tracing it out with a multimeter would be the safer more sensible option.

[gadgetgirl]

That's a decent chunk of power to be blowing a 7.5A fuse, definitely something abnormal like a short and not a fault on your part. What I would do is get rid of the second fuse holder so you just have the one with the 15A fuse in and then connect just the pigtail without it plugged into the device, if the fuse blows then you know the short is in that part of the cable. Of course tracing it out with a multimeter would be the safer more sensible option.

Thanks for the idea, it sounds reasonable. I just checked the SAE connector (nothing plugged into it) at the bike with the bike on. 13V and the polarity is as expected. I'll try plugging in just the pigtail.

[gadgetgirl]

Oh good grief, I realized my dumb mistake. I identified the long plastic side of the SAE on the bike is positive. So, when soldering the pigtail, I used the long plastic side as positive (plus the wire was red, plus that's the side the fuse was on from the factory). Well, SAE connectors don't work that way, do they? The accessory side polarity is a mirror, so I had the polarity reversed.

Moving on (nothing to see here), I have a fun new CarPlay/Android Auto toy on my SR/F for glanceable maps and a HomeKit on-screen button to control my garage door opener!

[TheRan]

Haha. That sounds like something I'd do too, just go with the colours without thinking too much about it. Lucky that it just blew the fuse and didn't damage the device. I'm actually surprised that happened, I don't know enough about electrical stuff to know why it would pull enough current to blow the fuse. I would have assumed either the device would have reverse polarity protection (as some battery powered things do) or the power would just go through it in the wrong direction and fry the first component in the circuit that couldn't handle it.

[2020_SRS_Commuter]

Ah you got it before I could tell you what you already discovered.
I've added many things to many rides, and the way I keep this straight is I remember that the positive conn is always female on the source side.