Magic Lantern - Autofocus- communication eror

[Kombi]

I have a T2i and installed magic lantern a while back.

I got my first error message slightly after that- Auto focus stopped, then communication error - clean contacts on lens. (exact wording slips my mind)

error was not common, but has became more regular. Yesterday I had the autofocus freeze up 4 times (no message) , and got a message a couple times.

I think this error has only been with my 24-105.

Now, I have not cleaned the contacts, but simply turning camera off then back on clears it up for a bit.
Few questions:
To clean the contacts what do I use?

Is there a way to check if it's my lens?

I'll jot down the actual message when it pops up. I thought it logged the message, but I can't find where.

Be a couple days before I can play with it either way.
I plan to try lens without ML for a few hrs, but if anyone has had similar issues I 'd love to hear some thought.

Thanks

[Busted Knuckles]

Try a different lens if you can. I was on vacation just after the 5dIII came out and a traveling companion had her 24-105 die on her. It may be the chip in the 24-105

[Kombi]

No solid update here
error has not repeated since this post.

[Kombi]

not sure how or why- or even if it's related, but just noticed only my top right AF points were lighting up ... maybe this added to my recent larger % than usual OOF shots.
can't select just the ones that were light up so?? anyway reset them now all points light up.

[Kombi]

More playing around- last few days only using 40mm previous days only 10-22... no focus issues.

yesterday using 24-105 within 30 min- Err 01 communication between camera and lens- clean contacts.

pointing to a problem with my 24-105.

[ahab1372]

so you think it might not be related to ML?

[Kombi]

so you think it might not be related to ML?

Correct I no longer believe it is related-- however I haven't tried it without ML yet.

I have not cleaned the contacts yet either- as I can have camera on and taking pictures for 20-30 minutes no error- i fail to see how they would suddenly get dirty.
As it is only with my 24-105L lens- I believe it is something in the lens when it warms up it ceases to function.


But while I'm thinking of it I'll load camera without ML so next couple days see if error is still present.

[Kombi]

Just to eliminate the variable, does it happen when the camera is coming out of sleep mode? have had the occasional instance of odd behaviour when taking a photo in a hurry that brought the body out of the power saving mode.

Only other item I can think to check is for a small rotation of the lens when it is locked in place. The pin and slot have tolerances and do wear.

It has happened when out of sleep mode, but has also been 2nd or third picture after focusing properly.

Lens mounts solidly, does not seem to rotate at all once locked in.

[Kombi]

Well went for another walk- without ML installed and got the error at end of walk
so 40 min of single pictures here and there no error, but once home , and dogs running around yard- few rapid pics and err 01 communication error.

So to me I think Busted Knuckles may have nailed the problem.
Something in lens (like a chip) once it starts working hard, overheats and stops.


I'll have to send for service likely.

[Sean Setters]

Good news: probably isolated the problem
Bad news: Servicing isn't cheap (if out of warranty)