Troubleshooting Issues
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      How to Troubleshoot Controller / Internal CAN in MirrorEye MKII

      Display Controller is locked to the button commands, how to troubleshoot the condition to locate the root cause

      The MirrorEye system includes a controller that provides access to the following functions: Day/Night mode, power folding, brightness adjustment, manual panning, and the driver's menu.

      The internal CAN protocol is used to provide communication between the controller and other system components, including the ECU, monitors, and wings.

      NOTE:  THIS TROUBLESHOOTING IS ASSUMING THE MIRROREYE SYSTEM MAIN HARNESS HAS PROPER CONNECTIONS ON KL15 & KL30 FOR POWER AND GOUND.  ALSO, THE TRUCK IS FREE OF CAN ISSUES. 

       

      Taking note of light indicators

      When powered on properly, a green light comes on back of the center scroll knob.

      In case of controller issues and its related features, follow the steps below:

      1. Mandatory tools
        1. Multimeter: will be used to measure the electrical properties like continuity function, output voltage (V) and resistance (Ω).
      2. Related Connectors
        1. Main harness "ECU" connector
           

          Related pinout table:
          Pin Color Description Meaning
          13 Yellow P_CAN2_H CAN2 High
          14 Green P_CAN2_L CAN2 Low

          Pin numbering order:
        2. Main Harness 4-pins Controller connector (Deutsch type)

           

          Related pinout table:

          Pin Color Description Meaning
          1 Red KL30 12v Power Supply to Controller
          2 White GND GND to Controller
          3 Green P_CAN2_L CAN2 Low
          4 Yellow P_CAN2_H CAN2 High

           

          Pin numbering order:

           

        3. Main Harness 2-pins Termination connector (Deutsch type)

       

      Related pinout table:

      Pin Color Description Meaning
      1 Yellow P_CAN2_L CAN2 Low
      2 Green P_CAN2_H CAN2 High 


      Pin numbering order:

       

      3. Main harness "Continuity" test for Open-Circuit CAN issues

      Warning

      Before performing the steps below, ensure that the electrical circuit you are testing has no power.

      If the truck is on, turn it off and turn master battery switch off, making sure there is no power coming from the battery. 

      Step Description
      a

      Set the multimeter to Continuity Test mode (-|-).
      b

      Insert one probe into the "4-pin controller" connector and the another into the "Termination" connector, following these combination and test one pair combination at a time:

      1. Main Harness (P_CAN2_H): "4-pin controller" pin 4 to "Termination" connector pin 1
      2. Main Harness (P_CAN2_L): "4-pin controller" pin 3 to "Termination" connector 
        pin 2
      c

      Insert one probe into the "4-pin controller" connector and the another into the "ECU" connector, following these combinations and test one pair combination at a time.

      1. Main Harness (P_CAN2_H): "4-pin controller" pin 4 to "ECU" connector pin 13
      2. Main Harness (P_CAN2_L): "4-pin controller" pin 3 to "ECU" connector pin 14
      Results If the multimeter beeps in each step above, a complete path (continuity) has been detected. 
       
       If the circuit is open, the multimeter will not beep. 
       
      If test results have no continuity on any step above, means an open circuit on the main harness, so it must be replaced.   Part Number of replacement harness can be requested from Stoneridge.  Will need to know the OEM Make and Model to determine correct harness.  For Freightliner will need to determine if the install is Pre-Wire or Retrofit

       

      4. CAN "Resistance" test for Controller/Internal CAN issues

      Taking note of CAN bus protocol

      A termination resistor is used to define a signal level during recessive bit transmission. 

      In a CAN bus, the resistance between CAN-High and CAN-Low should be about 60 ohms because there are two 120-ohm resistors in parallel.

      Step Description
      a If main battery switch was turned off in the previous test, keep turned off.
      b

      Check if the CAN termination resistor is properly connected.
      c

      Set the multimeter to Resistance Test mode (Ω).
      d

      Insert one probe into the "4-pin controller" connector pin 3 to pin 4.

       
      e

      The multimeter should show around 60 Ω resistance. 

      The acceptable range of this value should be around  +- 10%.

      If in the test above, the multimeter detects 120 ohms of resistance, measure the resistance directly at the termination resistor.

      If test results has no resistance, must replace the main harness's termination resistor.

       

      5. Main harness "DC Voltage" test for Controller issues

      Step Description
      a If main battery switch was turned off in the previous test, turn back on, and turn on the truck by key cycle.
      c

      Set the multimeter to "DC Voltage" mode (V)
      d

      Insert one probe into the "4-pin controller" connector pin 1 to pin 2.
      e

      The multimeter should show 12V Power Supply. 

      The acceptable range of this value should be around  +- 10%.

      If the circuit is open, the multimeter will show 0V Power Supply.

      If test results has no voltage, or results in an open circuit, must replace the main harness's termination resistor.

      If test results has the properly voltage, but connected to the controller the green backlight is not on, must replace the controller.

      6. Results and conclusion

      If all the tests performed above pass within spec ranges and the problem persists, the problem is in the joystick controller. Therefore, it will be necessary to replace the controller. 

      Release 1/7/2025 Revision x/xx/xxxx