3D touch Error:!! STOP called because of BLTouch error - restart with M999

Hy everyone, i just had the chance to install a cheap 3d touch, that i had laying around from a long time, to my ender 3 pro but i keep getting this error when i want to level the bed.

I have an mks gen l v1.0 motherboard with tmc2208 for XYZ and A4988 for E , tft28 v4 touchscreen, i have just flashed Marlin 2.1.2. Also i have 2 5015 fans installed.
i have followed several videos and tutorials for installing this touch probe, G28 sometimes work sometimes it doesn't, it homes X/Y then goes to the middle, raises up a little, stays, probe down, come up then probe again but at the first or second time for sure i will get this error sayng that is something wrong with the bltouch. If it manages to pass the G28 and i send G29, it preheats then goes to the first corner and the error pop after the first probe.

The wires that come out of it are soldered directly to the long ones that goes to the motherboard where i have some connectors that i have squishes a little so i can fell that they make good contact with the pins on the board. the connections are as in the diagram for the mks gen l, black/white to z end stop - gnd/sign, the others to the servo pins.

i also have messed with internals, the wires are soldered good inside, i have magnetized the magnet again and it atracts verry well so i have changed the termo tube and cut it a bit longer so that the set screw doesn't get in contact with the magnet directly but instead there is a bit of a distance enough for the coil to attract and reject it down. there was a play in the channel where the tip goes inside, the part with the magnet on top had room to go around since the hole in the plastic was bigger (hence the tip doesn't stay perfectly straight) and i have placed another layer of termo tube just on the top of the magnet so it fills a bit more the space but still has room to move a bit, it work even if it not perfectly straight with the plastic housing.

i have tried different distances for the set screw so that is closer/further away and i got better results when it was closer for that i am thinking that there might be a time that is exceeded when it takes a bit longer for it to engage when the screw is further up and has to move more. Or the magnetic field that measure something might be messed.

At some point i got the error "echo:endstops hit: z:-0.11" (and even bigger like ~ -1.X i think) wich i don't understand since it homes first with G28 then G29 gives me this. Isn't the 0 position the one first measured with G28? i haven't moved anything just the z axis moved by g code some mm up that is set in the firmware

Here are all the changes i have done in marlin so far for everything i have on going with the printer:
Changes in configuration.h marlin;

#define MOTHERBOARD BOARD_MKS_GEN_L //1113
#define X_DRIVER_TYPE TMC2208_STANDALONE
#define Y_DRIVER_TYPE TMC2208_STANDALONE
#define Z_DRIVER_TYPE TMC2208_STANDALONE
#define E0_DRIVER_TYPE A4988
#define DEFAULT_AXIS_STEPS_PER_UNIT { 80, 80, 400, 98.34 }
#define PREHEAT_BEFORE_LEVELING
#define LEVELING_NOZZLE_TEMP 200 // (°C) Only applies to E0 at this time
#define LEVELING_BED_TEMP 60
//#define SPEAKER
#define BLTOUCH
#define PROBING_MARGIN 20
#define NOZZLE_TO_PROBE_OFFSET { -56, -18, 0 }
#define MULTIPLE_PROBING 2
//#define MIN_SOFTWARE_ENDSTOP_Z
#define AUTO_BED_LEVELING_BILINEAR
checked if defined #define Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN
#define ENABLE_LEVELING_FADE_HEIGHT
//#define RESTORE_LEVELING_AFTER_G28
#define EXTRAPOLATE_BEYOND_GRID
#define Z_SAFE_HOMING
#define SLIM_LCD_MENUS
#define ENDSTOPPULLUP_ZMIN_PROBE
#define FAN_SOFT_PWM
#define SOFT_PWM_DITHER
#define SOFT_PWM_SCALE 1
#define PROBING_HEATERS_OFF
//#define WAIT_FOR_HOTEND
#define DELAY_BEFORE_PROBING 200


Changes in configuration_adv.h

#define BLTOUCH_DELAY 500
#define E0_AUTO_FAN_PIN 7 //for hotend fan
#define BABYSTEP_ZPROBE_OFFSET
#define BLTOUCH_FORCE_SW_MODE

Also if there is anything i have to modify for the serial com to work and not interfere with the tft screen would be great, the SERIAL_PORT -1/#define SERIAL_PORT_2 0 doesn't allow me to set to -1. It works now but just to be sure that they don't interfere.

I would really appreciate some help from anyone!
Regards, Alex!

Intermittent problems are hard to fix.

I don't think enabling BLTOUCH_FORCE_SW_MODE is a good idea. Better to leave it disabled.

Can you send it commands? If you enable PINS_DEBUGGING in configuration_adv.h then send it a M43 S command to start the probe test. It'll deploy/stow the probe multiple times and then ask you to manually trigger the BLTouch. Do it several times.

will do thanks , the stow deploy work every time i send the gcode M280 P0 S90/ M280 P0 S10 maybe just a little to slow, it is not a sharp retraction but ratter more smooth, i have magnetized and put a new tube on the magnet but maybe i have to tune the distance that i have left longer than the magnet to not stick but also be able to attract it to the set screw

Edited 1 time(s). Last edit at 01/27/2023 06:30AM by xxxmancs.

i have changed the following setting in the firmware and now i can do G28 and G28 successfully to get the grid pattern with values, also added a ferrite choke to white/black of the bl touch that goes to z min endstop, idk if it actually helps or not but for the moment if works!

//#define PREHEAT_BEFORE_LEVELING
#define Z_PROBE_SERVO_NR 0
#define NUM_SERVOS 3
#define SERVO_DELAY { 400, 400, 400 }
#define Z_CLEARANCE_DEPLOY_PROBE 10 //and others
#define Z_SERVO_ANGLES { 100, 0 } // Z Servo Deploy and Stow angles
#define USE_PROBE_FOR_Z_HOMING
//#define BLTOUCH_FORCE_SW_MODE
both enabled once, uploaded to probe firmware automaticaly then changed them back to undefined and reflashed
//#define BLTOUCH_SET_5V_MODE
//#define BLTOUCH_FORCE_MODE_SET


these are the fully changes i have made to the marlin firmware 2.1.2 from stock ender 3 pro config to work with my setup;



Changes in configuration.h marlin;

#define MOTHERBOARD BOARD_MKS_GEN_L //1113
#define X_DRIVER_TYPE TMC2208_STANDALONE
#define Y_DRIVER_TYPE TMC2208_STANDALONE
#define Z_DRIVER_TYPE TMC2208_STANDALONE
#define E0_DRIVER_TYPE A4988
#define DEFAULT_AXIS_STEPS_PER_UNIT { 80, 80, 400, 98.34 }
//#define PREHEAT_BEFORE_LEVELING
#define LEVELING_NOZZLE_TEMP 200 // (°C) Only applies to E0 at this time
#define LEVELING_BED_TEMP 60
//#define SPEAKER
#define BLTOUCH
#define PROBING_MARGIN 20
#define NOZZLE_TO_PROBE_OFFSET { -56, -18, 0 }
#define MULTIPLE_PROBING 2
//#define MIN_SOFTWARE_ENDSTOP_Z
#define AUTO_BED_LEVELING_BILINEAR
check if defined #define Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN
#define ENABLE_LEVELING_FADE_HEIGHT
//#define RESTORE_LEVELING_AFTER_G28
#define EXTRAPOLATE_BEYOND_GRID
#define Z_SAFE_HOMING
#define SLIM_LCD_MENUS
#define ENDSTOPPULLUP_ZMIN_PROBE
#define FAN_SOFT_PWM
#define SOFT_PWM_DITHER
#define SOFT_PWM_SCALE 1
#define PROBING_HEATERS_OFF
//#define WAIT_FOR_HOTEND
#define DELAY_BEFORE_PROBING 200
#define Z_PROBE_SERVO_NR 0
#define NUM_SERVOS 3
#define SERVO_DELAY { 400, 400, 400 }
#define Z_CLEARANCE_DEPLOY_PROBE 10 //and others
#define Z_SERVO_ANGLES { 100, 0 } // Z Servo Deploy and Stow angles
#define USE_PROBE_FOR_Z_HOMING

// nu #define SERIAL_PORT -1 (baudrate 115200)
// nu #define SERIAL_PORT_2 0
Changes in configuration_adv.h

//#define BLTOUCH_FORCE_SW_MODE
//#define BLTOUCH_FORCE_MODE_SET
//#define BLTOUCH_SET_5V_MODE

#define BLTOUCH_DELAY 500
#define E0_AUTO_FAN_PIN 7
#define BABYSTEP_ZPROBE_OFFSET
#define PINS_DEBUGGING //M43
#define ENDSTOPS_ALWAYS_ON_DEFAULT
these are some results from G29 executed 3 times in a row, i have to say that they aren't pretty accurate

0 1 2

0 -0.059 -0.259 -0.053

1 -0.146 -0.012 +0.015

2 -0.235 -0.358 +0.106

0 1 2

0 -0.032 -0.141 +0.049

1 -0.336 +0.114 +0.065

2 -0.157 -0.214 -0.150

0 1 2

0 -0.186 -0.120 -0.124

1 -0.079 +0.014 -0.017

2 -0.468 +0.008 -0.267

Great news!!

Yep, thanks for help!, Also recut the tube on the magnet, magnetized again and set the screw and for the moment i got these 2 readings that are pretty good for me

0 1 2
0 -0.115 -0.018 +0.050
1 -0.072 +0.012 +0.121
2 -0.108 -0.061 +0.003

0 1 2
0 -0.053 -0.001 +0.061
1 -0.067 +0.022 +0.127
2 -0.100 -0.054 +0.011

Edited 1 time(s). Last edit at 01/27/2023 11:27AM by xxxmancs.