<p>I have a Tevo Tarantula with a MKS Base 1.5 board and dual extruders.  I am running Marlin RC8 Tevo Community build for the dual extruder, large bed and SN04 sensor.  </p>

<p>All temperature sensors work and give accurate reading but <code>E1</code> when activated runs at 100% until the overtemps kicks in and shuts down the system.  Like I said, it reads proper temperatures through the thermistor it just won’t stop at the set temperature.  I checked the MOSFET and there is no obvious scorching or bad solder joints on the MKS board.  This leads me to believe it is a mix-up in firmware but, being a bit of a newbie on this, I am still getting familiar with G-code and Marlin.</p>

<p>I have confirmed the correct board is being referenced in firmware from <code>boards.h</code> but looking at <code>configuration.h</code> I just get confused.  What I am thinking is somehow/somewhere <code>E1</code> might be referenced as a fan that is just off or on.  Anybody have ideas?</p>

[{'answer_id': 4179, 'author': 'markshancock', 'author_id': 6417, 'author_profile': 'https://3dprinting.stackexchange.com/users/6417', 'pm_score': 1, 'selected': False, 'text': '<p>I am not sure what the hardware config is for the <strong>Tevo Tarantula</strong></p>\n\n<p>Make sure your <code>configuration.h</code> file is setup for your hardware.\nThe extruder defines are describe in <a href="https://github.com/JimBrown/MarlinTarantula/blob/bugfix-1.1.x/Marlin/Conditionals_LCD.h" rel="nofollow noreferrer">Conditional_LCD.h</a></p>\n\n<p>It looks like the <a href="https://github.com/JimBrown/MarlinTarantula/blob/bugfix-1.1.x/Marlin/Configuration.h" rel="nofollow noreferrer">configuration.h file</a> on GitHub is configured for a single extruder.</p>\n\n<p>For example, if you have 2 hotends; but, "HOTENDS=2" is not set then the I/O will not be configured for the 2nd hotend.  I just looked at the code and if <code>HOTENDS == 1</code> then the <code>MOSFET_D_PIN</code> will be used to control FAN1 (which sounds very similar to what you are describing that you are seeing).</p>\n\n<pre><code>  #if HOTENDS == 1\n    #define FAN1_PIN     MOSFET_D_PIN\n  #else\n    #define HEATER_1_PIN MOSFET_D_PIN\n  #endif\n</code></pre>\n'}, {'answer_id': 4198, 'author': 'Greenonline', 'author_id': 4762, 'author_profile': 'https://3dprinting.stackexchange.com/users/4762', 'pm_score': 0, 'selected': False, 'text': '<p>So, following on from <a href="https://3dprinting.stackexchange.com/questions/4177/dual-extruder-setup-in-marlin/4179#4179">Mark\'s answer</a>, in <a href="https://github.com/JimBrown/MarlinTarantula/blob/bugfix-1.1.x/Marlin/Conditionals_LCD.h#L298" rel="nofollow noreferrer">line 298</a> of <a href="https://github.com/JimBrown/MarlinTarantula/blob/bugfix-1.1.x/Marlin/Conditionals_LCD.h" rel="nofollow noreferrer">Conditional_LCD.h</a>, you would need to change:</p>\n\n<pre><code>#define HOTENDS       1\n</code></pre>\n\n<p>to</p>\n\n<pre><code>#define HOTENDS       2\n</code></pre>\n'}, {'answer_id': 4407, 'author': 'Jason', 'author_id': 7843, 'author_profile': 'https://3dprinting.stackexchange.com/users/7843', 'pm_score': 0, 'selected': False, 'text': '<p>I had a similar problem, my documentation was wrong and the heater &amp; thermistor were wired in backwards. Maybe recheck your wiring and even try reversing the temp sensor on your board.</p>\n'}]
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