# Gripper setup - servo issues **URL:** \ **Category:** Build/Make\ **Created:** [November 28, 2018, 12:55am UTC](https://discuss.bluerobotics.com/t/gripper-setup-servo-issues/3811 "2018-11-28T00:55:04Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![bhobson](https://avatars.discourse-cdn.com/v4/letter/b/977dab/32.png) [@bhobson](https://discuss.bluerobotics.com/u/bhobson)\ **Post date:** [November 28, 2018, 12:55am UTC](https://discuss.bluerobotics.com/t/gripper-setup-servo-issues/3811/1 "2018-11-28T00:55:04Z")
I’m attempting to integrate the Newton Gripper on an ROV running ArduSub 3.5.3 and QGroundControl v3.2.4-BlueRobotics-Rev6 per the instructions. The controller is an Xbox One and I’ve mapped buttons 0 and 3 (A and Y) to servo 3 max momentary and min momentary respectively. Upon pushing the buttons they’re highlighted on the joystick summary page. The shift key is disabled on both. On the pixlhawk side, no signal is being asserted on the bottom pin of the aux 3 output when measured with a DVM. When the gripper is plugged in nothing happens when either button is pushed. The voltage on the servo rail appears to be 5V. Has anyone ran into a similar issue? I can’t think of what to try next. Any ideas are appreciated. ---
**Author:** ![dheideman](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/dheideman/32/1555_2.png) [@dheideman](https://discuss.bluerobotics.com/u/dheideman)\ **Post date:** [November 28, 2018, 4:31am UTC](https://discuss.bluerobotics.com/t/gripper-setup-servo-issues/3811/2 "2018-11-28T04:31:27Z")
Hi Brett, Have you updated the firmware on your ROV to the latest version? The instructions for doing this can be found [here](http://docs.bluerobotics.com/brov2/software-setup/#ardusub). The _servo\_N\_max\_momentary_ and _servo\_N\_min\_momentary_ button functions are not implemented in older versions of ArduSub 3.5.3, meaning the ROV will not respond to the corresponding button presses even if you are running a compatible version of QGroundControl. ---
**Author:** ![bhobson](https://avatars.discourse-cdn.com/v4/letter/b/977dab/32.png) [@bhobson](https://discuss.bluerobotics.com/u/bhobson)\ **Post date:** [November 28, 2018, 10:36pm UTC](https://discuss.bluerobotics.com/t/gripper-setup-servo-issues/3811/3 "2018-11-28T22:36:00Z")
Yes. I followed those instructions and have tested the stable, beta, and dev versions of the firmware. None of them can seem to actuate the gripper. ---
**Author:** ![kklemens](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/kklemens/32/2247_2.png) [@kklemens](https://discuss.bluerobotics.com/u/kklemens)\ **Post date:** [November 28, 2018, 11:41pm UTC](https://discuss.bluerobotics.com/t/gripper-setup-servo-issues/3811/4 "2018-11-28T23:41:28Z")
Hi @bhobson, Can you try plugging into AUX Channels 1 or 2 and readjusting your button mapping for Servo 1 or 2? We check all the grippers for functionality before they leave our facility, but if you have something like a [servo tester](https://www.amazon.com/Consistency-Controller-Helicopter-Airplane-Throttle/dp/B07FQNZHG4/ref=sr_1_14?ie=UTF8&qid=1543448405&sr=8-14&keywords=servo+tester) you can verify functionality without the Pixhawk so we can narrow down what might be going on with your installation. ---
**Author:** ![bhobson](https://avatars.discourse-cdn.com/v4/letter/b/977dab/32.png) [@bhobson](https://discuss.bluerobotics.com/u/bhobson)\ **Post date:** [November 29, 2018, 12:32am UTC](https://discuss.bluerobotics.com/t/gripper-setup-servo-issues/3811/5 "2018-11-29T00:32:48Z")
Yes I did try all 3 channels with the same results. Do you have any experience plugging the pixlhawk directly into a computer to do servo testing? Otherwise I’ll get the amazon order rolling for the tester. Seems like a nice thing to have around. ---
**Author:** ![bhobson](https://avatars.discourse-cdn.com/v4/letter/b/977dab/32.png) [@bhobson](https://discuss.bluerobotics.com/u/bhobson)\ **Post date:** [November 29, 2018, 1:02am UTC](https://discuss.bluerobotics.com/t/gripper-setup-servo-issues/3811/6 "2018-11-29T01:02:46Z")
I found the problem. The aux pin config in the parameters tab under BRD\_PWM\_COUNT was set to no PWMS. Once I set this to 4 PWMS everything worked as expected. Thanks for your help! ---
**Author:** ![kklemens](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/kklemens/32/2247_2.png) [@kklemens](https://discuss.bluerobotics.com/u/kklemens)\ **Post date:** [November 29, 2018, 2:06am UTC](https://discuss.bluerobotics.com/t/gripper-setup-servo-issues/3811/7 "2018-11-29T02:06:22Z")
Excellent troubleshooting, glad its fixed!