Canon 24 - 105 L lens Needs some advise

I have this lens that is displaying a message with my new Canon Mk4 and wanted to see if anyone can give me direction to go. Message error...Err 01 Communications between the camera and lens is faulty clean the lens contacts I have done the contact cleaning a couple times now with no success please advise

Info that may help:
Which MkIV, 5D or 1D?
Does the lens do this on other cameras?
Does the camera do this with any other lens(es)?
Is the battery charged (>25%)?
Did this combination (camera/lens) EVER work properly?
Do you ALWAYS (every time) get the error message, or does it work sometimes?
How are you cleaning the contacts?

Try it on another camera. If it does the same, then send the lens in for repair.
You may also try with your extension tubes and tell us what happens.

Thanks for your advice. I have a 5D mk4 and this is the 1st time the 24 - 105 has been used on the camera I have used the 70 -200 all week with no issues at all. This seems to be the only lens that is affected, Any thoughts on the best Canon repair location??? Thank again

Its probably a failure of the internal ribon cable. It moves each time you zoom and eventually the cable breaks. Its quite a common problem with this lens and I had mine replaced about two years ago. Its a job for Canon and not particularly cheap I'm afraid to say.

Thank you for your insight Is this repair worth it based on a 5 year old lens?

Yes, it is the failed ribbon cable with almost complete certainty.
My 24-105 L experienced the same failure, also at the five year mark.
Since it is a stellar lens and apart from this failure worked as superbly as it did on Day One, I elected to pay the £220 repair fee of Canon UK authorised repairer H. Lehmann.

Bob F wrote in post #18203260
Thank you for your insight Is this repair worth it based on a 5 year old lens?

Yes. I have a 9 year old 24-105 that just had a failing aperture mechanism. I had Canon fix it, which cost me $225 including my CPS discount. To me it is worth it because my 24-105L is sharp and I like the lens.

And that's all despite also owning the 24-70/2.8 II.

I really appreciate your guidance on this lens. Thought it might be shot but will send off to Canon for repair. I use this lens as my walk around lens when in different cities. Has served me well over the years...

I had the ribbon cable replaced by Canon. It was worth it for me as I use the lens a lot. As I recall it was about $230. four years ago.

As others have mentioned it is probably the ribbon cable that is faulty. As an alternative to paying Canon to repair it you can find these ribbon cables elsewhere...there are listings on eBay right now at a considerable saving and the procedure for replacement can also be obtained if you search, there was a short while ago an individual offering the complete repair - again with a big saving. It depends whether you are confident enough to DIY. There is of course a risk of ending up with a plastic bag full of 24-105L bits however I would personally give it a go.