How do I know if my BLTouch is faulty or firmware is faulty? I just got the Ender 5 Plus with BLTouch set up today. I was having some massive issues and determined that my leveling was off because the BLTouch was flashing red and not connecting. When I turn on the printer there is about a 50% chance that it will probe correctly by deploying the pin and correctly retracting it. However, I'm having about a 75 to 90% fail rate on auto leveling where it is doing measurements. I've checked the wiring and it looks correct, but not sure what else to check.
The fixes I've seen say updating the firmware, but all show firmware at 1.70.0 BL. Mine is at 1.70.2 BL. So I'm not sure if there are more firmware updates to apply.
I do not know how to check which BLTouch I have. And I've been able to make it get to printing 2 times, but something is off because it is stringy at 1 point of the build on the first layer. No adhesion basically. So that is the problem I'm trying to fix, but can't get to it because the BLTouch fails so often on the first part. The only way I've found to fix the BLTouch consistently is turn off machine, pull the pin down, push it up, then turn on the machine again.
Is it possible this is a firmware issue or is just the BLTouch is likely faulty?
Try calibrating your Z offset
Based on this answer it sounds like the flashing red means there isn't enough clearance between your bed and your probe for it to operate.
You might try raising your Z axis up a bit to let the probe achieve the minimum clearance necessary for deploying the probe. My guess is that your Z-offset isn't quite right and it isn't raising up enough to allow that minimum clearance.
I recommend calibrating your Z offset and see if that resolves the issue.