Starting to hunt down what is causing a P16C8 code.

[CloverHillCrawler]

I had this happen to me before when coming down off Mount Storm, Full throttle on the highway, then when I go over an expansion joint on each end of a bridge, my F3 goes into limp home mode. I pull off the road, turn off the engine and remove the key, and everything goes back to normal.

This happened to me twice today on I-81 on my way to Maryville, Tn, where I am staying while clearing my head riding around the Smokies. The second time it happened, I was able to see the code before it reset. P16C8, I looked it up.

1. Potential Causes: Weak or failing battery - Low system voltage frequently causes false or secondary electronic control module (ECM) faults. Not this, put my Noco on the Genius 2 before I left. I will check voltage with my multi meter in the morning.

2. Loose battery terminals: Poor electrical connections can disrupt voltage stability to the ride-by-wire throttle system. Not this - Battery is Wrench tight with star washers. I will see if I can inspect the cabling coming off the TPS when I check voltage.

3. Throttle Position Sensor (TPS): Calibration drift or a need for a sensor relearn procedure. I'm thinking more this, but why with the combination of being at full throttle and hitting bumps? That's why I want to inspect the connection to the TPS.

Other than the 2 incidents on 81, I already did a ride to Deals Gap and back on the Dragon with no issues.

 

[Peter Aawen]

I've mentioned this before, had it happen to my RT, and I've seen it on a couple of other Spyders since, altho for different problems/no Codes, but there seem to have been a few battery cables that've been fitted to Spyders which have poor soldering securing the lugs onto the end of the main cables!

So even if checking the bolts holding those lugs onto the battery, the frame, or whichever terminal they are secured to can show they are all tight, have star washers, and fix onto bright metal, showing they are apparently fine; but if you grab the cable and try to wriggle it, things might be different! It's usually pretty apparent if the lug itself isn't secured all that well onto the cable, meaning that any bump you hit or movement in the cable can interrupt the power to whatever component or every component, usually momentarily, but not always!

With my RT, it was the lug on the end of the Main Earth cable to the Frame from the battery, the lug where it secures to the frame by the DPS, so I noticed the DPS dropping out intermittently first, but that soon progressed to everything! When it first happened, I checked all the terminals I could get at, including that one, for tight, good star washer enhanced connections onto bright metal, and like all the rest, it was good! It was only when I went back, after even more problems, to remove the battery that I noticed the cable end moving in the lug, where it should have been a firm, tight, connection, and I resolved that problem. After that, when owners present with these sort of intermittent problems, I've taken to checking all the cable to lug connections immediately after doing the 'Load test the battery FIRST' thing, and I've found at least one poor connection on a tad over half of the Spyders I've seen with these sorts of problems, and it doesn't seem to be more prevalent on any particular year/model either - early, late, V-twins, 1330's, old/lotsa miles, new/very few miles... duz'n matta! I'd guess at it being a quality control issue on behalf of whoever makes the cables, but our local dealer doesn't seem to be the least bit interested in pursuing that!

So, for my two bob's worth & this small saga, this may or may not be something contributing to your problem, but it's probably worth looking at/considering - because of that bump reaction, I'd guess there's something loose somewhere has to be the cause. But I'll still say that, as with all these sorts of weird electrical problems &/or odd codes, as always, it's still a good idea to load test the battery FIRST and check the battery voltage while actually cranking the motor over, and here's the cracked record bit - if you see anything much less than 12 volts while actually cranking, even with a lithium battery (or maybe especially? They're usually pretty good... ) there's an issue. Lower voltage than that while cranking likely means that for some reason or another, your battery isn't fully up to the task of running all the power hungry electronics/electrical demands of these power hungry machines!

Good Luck!

 

[Mikey]

The way he's explaining his issue you may have hit the nail hard on the head Peter!! You know, checking the lugs well has not been on my radar, but will be from now on! Thanks!!