Can’t drive south?

I seem to have a strange problem. I’m using v5 with cmps14. It drives incredibly straight east, west and north but the heading jumps all over the place if I go south. It’ll go fine for a few seconds then try to toss me out of the cab.
I’m guessing it’s probably something with the CMPS?
Anyone have any ideas?

I am having same problem going East. Just noticed yesterday. Having same problem today in different field. Ignored roll, that fixed for a few rounds. Tried to move fusion to 100% gps. Heading still irratic. Shouldn’t this ignore imu?

I also tried moving the slider all the way to GPS, but it didn’t help. I also discovered the same problem if I went uphill (not mild slopes, but hills) going west. Are you also using the cmps14? I’m wondering if certain orientations of my tractor cause em interference. It sounds like that wouldn’t happen with a bno085 because it doesn’t use the magnetic reference, but nobody can seem to get one of those. I ordered some faraday cloth on Amazon. I’m going to try wrapping it around my cmps box and see if that helps. But I’ve finished seeding anyway, so it might be next year’s problem.
I also have the same setup in a different tractor that never has a hiccup. That’s why I’m thinking interference. I can’t see a better place to mount it in the problem tractor so I’ll try the cloth or a bno if I can ever get one.

Going up hill. Are you sure you have Imu mounted correct .sounds like turned 90 degrees

@Larsvest I’m sure it’s mounted right. Pins, on the forward side pointing up. Roll reads correctly too.
Also doesn’t happen going uphill to the east or north.

Ok. So doing uphill or down hill, doesn’t change roll!

No, only to the extent that it should. As in a little roll to the side it should but definitely not reading how steep my climb is.

I found yesterday in v5.5, using fix to fix, on Articulated 4WD tractor GPVTG was still required. It would not draw properly. Once reactivated everything worked awesome.

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I ran the same problem tractor today pulling a land roller which had no electronics obviously and it acted much better. Still jumped a couple of times going south in the same field that it went crazy in before constantly. Then on to hills and still the odd jump there again going west, but again much less. This makes me think that the problem has to be interference.

Yes cmps14. No problems headed East in first 2 fields, but something changed. First field I noticed, it was right in middle of field same spot would dive South, then straighten out. I thought it was the local antenna towers, or railroad tracks. I was right next to both. But it only got worse.

@Kevin are your fields flat? Or are you having the problem when you come to a hill too? When my faraday fabric shows up I’ll test that out and see if it makes any difference. I’m pretty sure that a bno085 would solve it.

They are flat. Haven’t been on hills much to test.

My faraday fabric showed up yesterday. The weather here is miserable today, maybe I can find some grass to test on.

I have the same problem only on one tractor the other one is fine. The setup is the same on both of them.

I saw on the forum someone mentioned that they just extended the wires and the CMPS14 on top of the box in a small metal box to act as a faraday cage. In my opinion, this is a good solution because CMPS14 mounted on the PCB is the main issue.

CMPS14 needs clear magnetic field this one direction problem maybe comes from PCB being in front of earth magnetic field that goes from geografic south pole to north pole and in other 3 directions CMPS14 is exposed first to field and PCB and other factors cant interfere.

Good test is just rotate PCB box and see if it changes behavior. Or move it to roof away from metal and interference.


My cmps is using a separate nano, not mounted on the pcb. Although they did end up being only a couple feet apart… maybe still too close?

Mine is on pcb. Probably would fix it relocating. Yesterday worked fine headed East, Same field had trouble in. Would be nice to be able to turn off IMU in fusion when it goes crazy. Could troubleshoot sitting still. Gps heading was locked without moving, but screen was twitching like crazy. And heading was varying + - 2.5deg.

I am facing the same problem. Something that caught my eye is that IMU starts going crazy when I turn on the autosteer (engage the motor).

I kept an eye on mine as I was driving by hand with the autosteer turned off and it was jumping around just the same.

Waiting to hear your thoughts on the Faraday cloth to fix this problem. My cmps14 finds everything. Buried electric wires to pivot. Buried metal. Twitches when facing electric transfer station 5km away.