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Quick Tip: Harley-Davidson® Functional Tests

Applies To: APOLLO-D8™, APOLLO-D9™, ETHOS® Edge, ETHOS® PRO, ETHOS® Tech, MODIS Edge™, MODIS Ultra™, SOLUS Edge™, SOLUS Ultra®, TRITON-D8®, VERUS® Edge, ZEUS®

Vehicle: Harley-Davidson Ultra Classic. If you have a problem with a gauge cluster, how can you quickly figure out if it's a cluster problem or a sensor? In this Diagnostic Quick Tip, National Field Trainer Jason Gabrenas shows you how to perform some bi-directional functional testing on a Harley-Davidson using a scan tool.



Diagnosing some electrical problems on any vehicle can be difficult sometimes.

Maybe I have a problem somewhere in my instrument cluster. Is it the actual cluster itself or is it one of the sensors feeding the cluster?

You can do Functional Tests in order to see where the problem might lie and now in our software you can do that with Snap-on tools with Harley Davidson.

Let's run through a couple of different functional tests on this bike right here.

First we're going to go under Speedometer, ID the ECU, and we've got Functional Tests so let's go there and let's do some Actuator Tests.

Let's say the battery indicator, maybe we're not sure if that's working correctly. So we can go in there and hit yes, it's going to load in to the test, click on light, turns on, go to off light, turns off.

We know the battery light's working. Let's go to the speedometer. Maybe we're not sure, is the speedometer working 100%? Maybe something is wrong with the motor in there.

So we'll go turn that on. We'll load in the test again, hit up, needle goes up, hit down, needle goes down. So we know the speedometer is working. Let's do a tachometer now and go into the test. Same thing. Up. Needle goes up, down. Needle goes down.

So we know those gauges in that light are working because we've tested through that.

Let's check one more thing. Let's go to the LCD segment checks. This will check to see if the odometer is displaying properly.

So go in there. Hit yes, it's going to light up. It's going to put a bunch of characters up there and test all the segments. Everything looks good. Everything seems to be functioning properly.

So this is a good way to narrow down whether or not you have a problem in the actual cluster itself or if it's some other problem in the vehicle.

Last Updated: August 14, 2020

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