Long IMU warmup = Compass issue?

[marcus_canada]

I have a previously owned Phantom which takes 2-3 minutes to go through the IMU "warm-up" sequence, every darn time it takes a battery, it's always been that way. I have no illusions that it's anything to do with temperature, it does it in a warm house as well and none of my other ones do it - It's a self test sequence which is having problems for sure.
It's a PITA but, meh, you get used to being the last guy in the air hahaha.

So anyway, it OFTEN complains that it wants the compass dance as well. Like, the other day I had to do it twice before it would let me take off, then as soon as it was up it asked me again for it, so I had to swing it round, bring it in and do another one - Grrrrrrr

I know that some other guys have Friday-Afternoon Naza's which have long IMU "warm-up" times and was wondering if any of them have compass issues too? Maybe it's the Compass which is the root cause here....

 

[Nvr2fst]

My original Phantom did this after the big update. I figured they changed it to make sure everything was a go before you took off. Maybe because of peoples fly off claims. Yeah since that update it became a stupid long wait compared to what it was. I never had a problem with the way mine was before the update. You know, the update that changed all of the LED light codes.

So I do not see it as a compass issue.

 

[anotherinfidel]

I have like a 5 min IMU warmup every time. Is this normal?

 

[Fplvert]

I've found doing a cold IMU calibration will speed up the warm-up time. Place the bird outside, or in the refrigerator for twenty minutes, then place it on a level stable surface and immediately begin the IMU calibration.
Startup should then only take about 1 minute. Give that a whirl!