# How to access AUX channels 4-5 **URL:** \ **Category:** Blue Robotics Products\ **Created:** [April 18, 2019, 3:05am UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870 "2019-04-18T03:05:30Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![etienne](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/etienne/32/1942_2.png) [@etienne](https://discuss.bluerobotics.com/u/etienne)\ **Post date:** [April 18, 2019, 3:05am UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/1 "2019-04-18T03:05:30Z")
Hi guys, Desired connections on the pixhawk are: Primary 1-8 : Thrusters in heavy configuration Aux: 1: Tilt1 2: Tilt2 3: Light1 4: Light2 5: Newton gripper 6: water sensor I read in the document that only servo 1,2 and 3 are available to be controlled via buttons. Is there a reason for this? How can I access servo control for 4,5? Cheers, E. ---
**Author:** ![jwalser](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/jwalser/32/2234_2.png) [@jwalser](https://discuss.bluerobotics.com/u/jwalser)\ **Post date:** [April 18, 2019, 3:11am UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/2 "2019-04-18T03:11:38Z")
Lights and camera tilt function can go on any servo channel. The \_servo\_1 etc joystick buttons can only be applied to servos 1-3. The reason is to keep the list of options reasonably short. This means that your gripper must be on channel 1-3. Also, the water sensor must be configured as gpio instead of pwm via the BRD\_PWM\_COUNT parameter. This doesn’t allow for a single gpio, the finest granularity is two at a time :(. ---
**Author:** ![etienne](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/etienne/32/1942_2.png) [@etienne](https://discuss.bluerobotics.com/u/etienne)\ **Post date:** [April 18, 2019, 3:17am UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/3 "2019-04-18T03:17:55Z")
Yeah at present I am only connected on aux 1,2,3 Not sure I am following. Ch4 and 5 are unusable? ---
**Author:** ![jwalser](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/jwalser/32/2234_2.png) [@jwalser](https://discuss.bluerobotics.com/u/jwalser)\ **Post date:** [April 18, 2019, 3:22am UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/4 "2019-04-18T03:22:00Z")
The lights and camera tilt may be used on 4 5 and 6. If you use a leak detector on the servo header, you can’t use 5 for pwm (you could put the leak sensor on analog input) ---
**Author:** ![etienne](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/etienne/32/1942_2.png) [@etienne](https://discuss.bluerobotics.com/u/etienne)\ **Post date:** [April 18, 2019, 3:30am UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/5 "2019-04-18T03:30:36Z")
Thanks for this. How do I control the camera and light on these channels being servos are not available in the joystick buttons? Which analog input are you referring to and how do I get this up in QGC? Cheers, E. ---
**Author:** ![jwalser](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/jwalser/32/2234_2.png) [@jwalser](https://discuss.bluerobotics.com/u/jwalser)\ **Post date:** [April 18, 2019, 3:40am UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/6 "2019-04-18T03:40:44Z")
Set the camera and lights up on the camera and lights setup page, they are configured differently than the gripper, which is why the limitation only applies to the gripper. Look at the LEAK\_PIN parameter: [Redirecting...](https://www.ardusub.com/operators-manual/full-parameter-list.html#leak1pin-pin-that-leak-detector-is-connected-to) ---
**Author:** ![jwalser](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/jwalser/32/2234_2.png) [@jwalser](https://discuss.bluerobotics.com/u/jwalser)\ **Post date:** [April 18, 2019, 3:41am UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/7 "2019-04-18T03:41:01Z")
And BRD\_PWM\_CNT ---
**Author:** ![etienne](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/etienne/32/1942_2.png) [@etienne](https://discuss.bluerobotics.com/u/etienne)\ **Post date:** [April 18, 2019, 3:50am UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/8 "2019-04-18T03:50:19Z")
thank you Jacob. I’ll have a look at it when I am back in the office. ---
**Author:** ![Stihus](https://avatars.discourse-cdn.com/v4/letter/s/fbc32d/32.png) [@Stihus](https://discuss.bluerobotics.com/u/Stihus)\ **Post date:** [January 4, 2022, 1:44pm UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/9 "2022-01-04T13:44:14Z")
Hi, I have a follow up question about this. How do I solve the wiring if I want to move the leak detector to ADC 3.3V? It is thre wires coming from leak detector board and the ADC 3.3V input on Pixhawk have 5 pins, which wire goes where? ---
**Author:** ![EliotBR](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/eliotbr/32/6937_2.png) [@EliotBR](https://discuss.bluerobotics.com/u/EliotBR)\ **Post date:** [January 6, 2022, 11:27pm UTC](https://discuss.bluerobotics.com/t/how-to-access-aux-channels-4-5/4870/10 "2022-01-06T23:27:20Z")
Hi @Stihus, The [ArduPilot Pixhawk Overview](https://ardupilot.org/copter/docs/common-pixhawk-overview.html#adc-3-3v) specifies the following pinout: > [@ArduPilot - Pixhawk Overview](#): > > ### ADC 3.3V > > | Pin | Signal | Volt | > | --- | --- | --- | > | 1 (red) | VCC | +5V | > | 2 (blk) | ADC IN | up to +3.3V | > | 3 (blk) | GND | GND | > | 4 (blk) | ADC IN | up to +3.3V | > | 5 (blk) | GND | GND | It also includes some additional detail about the [Pixhawk analog input pins](https://ardupilot.org/copter/docs/common-pixhawk-overview.html#pixhawk-analog-input-pins).