"temp sensor defect" message with megatronics v3

I installed and configured firmware 0.91 repetier a Megatronics V3. The extruder includes a thermocouple type K. The hot bed for a 100k thermistor. When I connect to the printer from Repetier-Host I get a message:
Extruder 0: temp sensor defective
hot bed: Temperature sensor defect
499º In the extruder temperature indicator
No warm bed appears.

Any help is welcome :)



  • You know that thermocouples can not be put where thermistors are connected? They need a special chip and other sensor pins. Make sure you have set them correctly. Same for the bed. Bed is by default on the second thermistor input configured, so you must connect it there or change pin number to the one you used.
  • Thanks for the reply.

    I put everything up.

    I modified the pins according to the datasheet of megatronics v3.
    In pins.h the configuraqción I have done is:

    * MegaTronics v3.0
    D0 RXD                D38Y+ End stop
    D1 TXD                D39 LCD6
    D2 Extruder 0         D40 X+ End stop
    D3 Z axis enable      D41 Y- End stop
    D4 Y axis enable      D42 Keypad D42
    D5 Y axis step        D43 Keypad shift clock
    D6 Fan 1              D44 Keypad encoder 2
    D7 Fan 2              D45 Keypad encoder 1
    D8 Extruder 2         D46 AUX3-6
    D9 Extruder 1         D47 AUX3-5
    D10 Heated bed        D48 AUX3-4
    D11 Z axis direction  D49 AUX3-3
    D12 PS-on             D50 MISO
    D13 Debug LED         D51 MOSI
    D14 LCD 4             D52 SCK
    D15 LCD 7             D53 SS
    D16 Z axis step       D54 AUX1
    D17 Y axis direction  D55 AUX1
    D18 Z- End stop       D56 SDOUT
    D19 Z+ End stop       D57 X axis direction
    D20 SDA               D58 X axis step
    D21 SCL               D59 X axis enable
    D22 E2 axis step      D60 E2 axis direction
    D23 E2 axis enable    D61 Speaker
    D24 E1 axis direction D62 Thermocouple 4
    D25 E1 axis step      D63 Thermocouple 3
    D26 E1 axis enable    D64 Thermocouple 2
    D27 E0 axis direction D65 Thermocouple 1
    D28 E0 axis step      D66 Thermistor 4
    D29 E0 axis enable    D67 Thermistor 3
    D30 LCD5              D68 Thermistor 2
    D31 LCD enable        D69 Thermistor 1
    D32 LCD RS           
    D33 Keypad D33
    D34 Keypad shift out
    D35 Keypad shift LD
    D36 Keypad D36
    D37 X- End stop
    #if MOTHERBOARD == 703
    #define KNOWN_BOARD 1

    #ifndef __AVR_ATmega2560__
    #error Oops! Make sure you have 'Arduino Mega' selected from the 'Tools -> Boards' menu.

    #define ORIG_X_STEP_PIN 58
    #define ORIG_X_DIR_PIN 57
    #define ORIG_X_ENABLE_PIN 59
    #define ORIG_X_MIN_PIN 37
    #define ORIG_X_MAX_PIN 40 //2 //Max endstops default to disabled "-1", set to commented value to enable.

    #define ORIG_Y_STEP_PIN 5 // A6
    #define ORIG_Y_DIR_PIN 17 // A0
    #define ORIG_Y_ENABLE_PIN 4
    #define ORIG_Y_MIN_PIN 41
    #define ORIG_Y_MAX_PIN 38 //15

    #define ORIG_Z_STEP_PIN 16 // A2
    #define ORIG_Z_DIR_PIN 11 // A6
    #define ORIG_Z_ENABLE_PIN 3 // A1
    #define ORIG_Z_MIN_PIN 18
    #define ORIG_Z_MAX_PIN 19

    #define ORIG_E0_STEP_PIN 28
    #define ORIG_E0_DIR_PIN 27
    #define ORIG_E0_ENABLE_PIN 29

    #define ORIG_E1_STEP_PIN 25
    #define ORIG_E1_DIR_PIN 24
    #define ORIG_E1_ENABLE_PIN 26

    #define ORIG_E2_STEP_PIN 22
    #define ORIG_E2_DIR_PIN 60
    #define ORIG_E2_ENABLE_PIN 23

    #define SDCARDDETECT -1 // Ramps does not use this port
    #define SDPOWER -1
    #define SDSS 53

    #define LED_PIN 13

    #define ORIG_FAN_PIN 6 //FAN 1
    #define ORIG_FAN2_PIN 7 //FAN2

    #define PS_ON_PIN 12
    //#define KILL_PIN -1

    #define HEATER_0_PIN 2 // EXTRUDER 0
    #define HEATER_1_PIN 9 // EXTRUDER 1
    #define HEATER_2_PIN 8 // EXTRUDER 2
    #define HEATER_3_PIN 10 // heater bed

    Temperature sensors



    #define TEMP_0_PIN 15 // Extruder 1
    #define TEMP_1_PIN 14 // Extruder 2
    #define TEMP_2_PIN 13 // Extruder 3
    #define TEMP_3_PIN 12 // Heated bed

    #define BEEPER_PIN 61 // Beeper on AUX-4
    #define SDSUPPORT true // sd card reader on board

    // #define UI_DISPLAY_RS_PIN 32
    // #define UI_DISPLAY_ENABLE_PIN 31
    // #define UI_DISPLAY_D4_PIN 14
    // #define UI_DISPLAY_D5_PIN 30
    // #define UI_DISPLAY_D6_PIN 39
    // #define UI_DISPLAY_D7_PIN 15

    //buttons are directly attached using AUX-2
    ////encoder A 59
    ////encoder B 64
    ////encoder click 33 //the click

    #define SCK_PIN 52
    #define MISO_PIN 50
    #define MOSI_PIN 51


    Best regards
Sign In or Register to comment.