Rear camera not working - iPhone 5s

I recently received an iPhone to fix with camera issues, I have replaced the rear camera which has made no difference.

The front camera functions as intended, when the camera is switched to the rear view it is blurry with the previous image of the "selfie". Occasionally the display where the image would normally be goes blue. I was wandering if anyone else had come across this and has any advice.

Thanks in advance!