CANNOT figure out this DPS issue - intermittently cutting out on corners. Any clues?

new to me 2008 GS, having DPS issues, dealer it came from put a new DPS unit and battery in before I bought it,
The DPS works normally, but when going around a corner aggressively, such as turning on a new road, the DPS will cut out, seems to be mostly right hand turns. and then the check DPS light comes on. If I shut it off, wait 15 seconds, and restart, the light is off and DPS works fine again. sometimes I can ride it a hundred miles with no issues until I take a corner hard, throws code P0551, and one time, a C1290, (VCM Voltage Failure?) Do these DPS units require more power the harder you corner? I have cleaned the battery connections, charged battery, and cleaned ground under seat. going to clean ground next to DPS, and if no change, have the steering angle and YAW centered at a dealer, as advised by someone on another group.
Anyone else have any other clues as to what may be the issue here?

Anyone in Michigan or northern Indiana have access to BUDS?

The DPS units really ARE power hungry, so if the battery that was recently installed wasn't properly charged BEFORE installation (ie. 8 hours or so on a Battery Charger, & NOT just on a Battery Tender! :banghead: ) then that could be at least contributing to the symptoms you're describing?! :dontknow:

However, if the battery was charged properly before installation & it's still in good nick, then it could quite possibly be something as simple as a loose terminal or the one that got me on my 2013 RT, a loose Earth Connection behind the frunk where the 2013+ batteries are mounted, where a cable direct from the Battery Negative Terminal to an Earth point on the frame shared with the DPS and accessed thru the LH Steering Gear tunnel is found! :mad: Due to the amount of movement that Earth strap was subject to when I installed the new & properly charged battery thru the panel in the frunk, not only wasn't the bolt holding the Earth Lug onto the frame tight anymore, but the solder holding the lug onto the end of the cable had largely broken away, so every time I turned the wheel hard enough, the cable flopped around a bit, lost the Earth connection, and the DPS would drop out in much the same way as you describe! Made for a few exciting moments, I can tell you! :shocked:

So I initially cleaned & tightened that Earth connection onto the frame, but still got some less frequent DPS cut-outs.... after which I discovered the 'not great solder connection' for the Earth Lug on the end of the cable. A bit of heat resolved the solder problem; and another star washer (similar to those I'd just added to the battery terminals :p ) to make sure that lug got a good, tight, 'never to work loose again' connection to the frame resolved the rest. Haven't had any DPS initiated butt clenching moments since. :thumbup:

Maybe none of this has anything to do with the cause of your particular DPS problems, but I'd suggest that it won't hurt if you make sure your battery is PROPERLY charged and that you check out; clean; fit star washers; and tighten the battery terminals AND every Earth point you can find! :lecturef_smilie: I don't know if your 2008 has the same DPS Earth point on the frame behind the frunk as the 2013+ models, but I do know that the Earth point to the frame under the seat near where your 2008's battery is mounted is VERY EASILY stripped or otherwise compromised, so checking that out and making sure it's tight and doing the job properly is very important! Just don't over-tighten it and strip the riv-nut's thread &/or tear it out of the frame, cos if you do either/both it's a right pain to get a nut in behind that bit of frame to get that Earth Strap tight enough to ever work properly again!! :cus:

Good Luck! :cheers:

Yeah Rocket. What Peter said. We're not making up this stuff. A new battery needs to have an activation charge after the acid is added. It's right there on the spec sheet, and yet techs continue to just skip over that, saying that it isn't necessary. It is. So, before you worry about sensors and BUDS, get out your smart charger, set it to AGM, set it to 2 amps, start a charge and come back the next day.

If you're a numbers guy - The amount of assist increases as the steering force you are exerting on the handlebars increases. That is sensed by the Torque Sensor. It's an electro-magnetic assist, not a hydraulic assist. Look at the fuse size for the DPS motor. So, drawing 25 to 30 amps when using it hard is not uncommon. Look at all of your other electrical loadings that you might have running. And now realize that your 500 watt magneto isn't putting out anything close to 500 watts when RPM is low in the corners. If the battery doesn't have that reserve of energy in it, the voltage drops. By design, the DPS begins to shutdown at 11.5 volts. And you also received a VCM low voltage. So, this pretty much has all the earmarks of a battery that wasn't properly charged.

Regarding sensors - if it comes down to going that direction - the Yaw sensor doesn't have a lot to do with the DPS. That's more of a VCM function. The two sensors associated with the DPS are the Steering Angle and the Torque Sensors. They need to be zero-ed but should have been when they replaced the DPS.

Edit: About the Yaw Sensor specifically, Rocket. When you look at its output signal in BUDS, someone needs to be sitting on the Spyder in the seat for an accurate reading. That’s the correct procedure for checking it and resetting it. Techs will just look at the output and hit the Reset button, thinking it needs reset. Unless you’re getting bogus or pre-mature VSS interventions, I wouldn’t mess with the Yaw Sensor.

This is probably not your issue. But the DPS has an overheat protection circuit that kicks in and shuts the DPS down if it gets too hot. Usually, an overheat is created by low voltage. When voltage is low, amp draw increases which creates more heat. I agree with those who have already posted. My first guess would be a voltage/battery issue.

Excellent information everyone! I GREATLY appreciate it! I love to be educated on how things I am unfamilar with operate, helps m with diagnostics. I will be looking into all of this this weekend (hopefully), going to make dang sure the connections are all clean and tight, and I will get the battery on a good charger, its currently on just a tender, but sounds like i need to have it on a good charger.

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Originally Posted by the496rocket

Excellent information everyone! I GREATLY appreciate it! I love to be educated on how things I am unfamilar with operate, helps m with diagnostics. I will be looking into all of this this weekend (hopefully), going to make dang sure the connections are all clean and tight, and I will get the battery on a good charger, its currently on just a tender, but sounds like i need to have it on a good charger.

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Whatever " Charger " you choose ... It should be labeled as a " Maintainer " type ... these are generally LOW amp circuitry that will SHUT OFF automatically when the battery is fully charged .... Even a low amp charger or tender can literally FRY a battery if it doesn't have an auto shut off feature ..... Mike :thumbup:

Update on this issue, it appears to be resolved, we charged the battery, and cleaned all the grounding points. But what I am 99% sure the issue was, when we removed the frunk to get at the front grounding point near the DPS, I found what looked to be like a homemade grounding wire that went from the frame ground to the main ground at the top of the DPS unit. That wire was a 12-14 gauge wire, but obviously the power wire is about 6-8 gauge. Looking up the parts diagram shows that ground wire to also be 6-8 gauge. So someone put this wire in there for some reason, and obviously it can't handle the amperage that the DPS pulls. We made a new wire from 6 gauge, and a test ride confirms that it is fixed.

Quote:

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Originally Posted by the496rocket

Update on this issue, it appears to be resolved, we charged the battery, and cleaned all the grounding points. But what I am 99% sure the issue was, when we removed the frunk to get at the front grounding point near the DPS, I found what looked to be like a homemade grounding wire that went from the frame ground to the main ground at the top of the DPS unit. That wire was a 12-14 gauge wire, but obviously the power wire is about 6-8 gauge. Looking up the parts diagram shows that ground wire to also be 6-8 gauge. So someone put this wire in there for some reason, and obviously it can't handle the amperage that the DPS pulls. We made a new wire from 6 gauge, and a test ride confirms that it is fixed.

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Excellent work!!!

Now that's some dedicated perseverance! Much impressed! Doing your own work can be very frustrating. But very rewarding at the same time.

You did good!

and thank you for coming back and telling us what the problem was, and the remedy.:thumbup::thumbup::thumbup:

Great job...

Thanks everyone, was a tough one but glad its all fixed now. Now just need to change the water pump oil seal...

https://www.spyderlovers.com/forums/...eal-any-advice

Well I spoke too soon. Ride it for an hour last night, and made a quick right turn into a parking lot towards the end of the ride, and the DPS went out almost immediately. :mad: So back to the drawing board. I’m still thinking voltage issue. Same code came back. p0551, no VCM voltage code but that only came on once before. We haven’t had it on a charger for a couple weeks now, and I’m just wondering if the battery is just slowly dropping off or something. Got ridden about twice since we thought we had it fixed before. Needless to say I was pretty annoyed last night.

Any update?

Still trying to figure it out. May have to have it scanned at a dealer which I’m trying to avoid. Might just get my own buds scanner before I do that.