5d Mark IV Blinking red in Viewfinder

[Sesshoku]

Hello Community. I've had this just start happening to my 5D Mark 4, and I'm not sure if a menu setting got changed or if there is a problem with this camera. I can't find anything in the menu that I can use to stop it from happening, so maybe some of you have experienced it and can advise on a fix before I send it in to CPS. 

When in photo mode, I now get a red flashing in the viewfinder that I've never had before. I do have the focus point illumination turned on, but it has always been on. The focus points and the battery symbol flash all together. It's actually like the full screen flashes red at a fairly quick rate. I tried using the camera with a fully charged battery and got the same situation. I have not noticed this happening in video mode, but I generally use an external monitor when shooting video. Can anybody help me figure out what is happening?

Chad

 

[shadowsports]

Greetings,

Please answer the following:

-Are you using Canon brand batteries?

-Does this happen with one lens or any attached lens?

-Do you have any accessories connected to the camera?

The issue appears to be related to focus acquisition or lack of, but we may have other ideas depending on your answers to the questions above.  

Start by performing a factory reset, all settings, including custom functions.  

We can comment further once we have more information from you.

[Sesshoku]

1. Yes, Canon LP-E6N batteries 

2. It happened with both lenses I've used since this began. I was first using my Sigma 35mm 1.4 ART lens when I first noticed it. Then I tried using my Canon EF 85mm f/1.4 then my 16-35mm f/2.8 and same thing. 

3. No other accessories attached at the time I noticed it. 

[jrhoffman75]

A posting on DPReview about battery icon flashing red was resolved by cleaning the contacts.

[deebatman316]

What lens is being used 3rd Party or Canon. What flash if used. Any other accessories attached to the camera.

[Sesshoku]

When I first noticed it, I was using a Sigma 35mm f/1.4 lens. But it does the same thing with my Canon EF 85mm and 16-35mm lenses. No other accessories attached when it began. 

[shadowsports]

Greetings,

Have you reset the camera to defaults?  Main and custom settings.  This should be done first.

Have you inspected the terminals in the battery compartment as jrhoffman75 suggested?

Please do this, connect one of the lenses, put the camera into [A+] go outside and take a photo.  

If the viewfinder still blinks red, your camera will require service.  

[Sesshoku]

No, I am not near my camera right now. That will be something I attempt this weekend. Thank you for your response. I hope it works.