Asked — Edited
Resolved Resolved by Dave Schulpius!

H_Bridge Wiring Question


I found an issue with the factory wiring with my Roli's H-Bridge wiring. When I was doing the h-bridge test I noticed that the unit wouldn't move. Upon inspecting the h- bridge wiring I noticed that the red and black wires coming from the on/off switch were wired wrong on the h- bridge. The red and black wires were off by one screw slot. I also noticed a burning smell, but couldn't see anything that was burnt. After correcting the wiring error,I still can't get the unit to move. I'm wondering if the wiring error blow out the h- bridge.

Is there any diagnostic that I can do to confirm this, and if the h- bridge is bad how do I go about getting it replaced under warranty?

Thanks in advance for your help


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Yes, sadly the h-bridge is most likely bad now. The hot wire is going straight into the ground port of the h-bridge. Epic fail! eek

Your going to have to get a now one. It's an issue that has been talked about before. The people who assembled your unit screwed up. As bborastero pointed out; you need to use the Product Warranty section on the Contact Us page and EZ Robot will make it right.

It sucks that you have to now wait a week or more till the now H-Bridge arrives to use your robot. tired


They seem to be stocking some replacement parts in Canada now. I got the missing roation servos from my Scorpion kit overnight delivery from EZ-Robot headquarters, so it might not take too long.

It they tell you it will be more than a few days email me (address in my profile). I have a spare H-bridge I could express mail you and you can have EZ-Robot send the replacement to me.



Hello, Thanks for all the replies to my problem. I believe that as Dave says my h- bridge is fried from the wiring error made by the factory. I'm going to request a replacement from ez-robot. Will update this post if this resolves the issue.

Thanks, Calvin



I sent in a warranty request on 12/28/2014 and I haven't heard back from ez-robot yet. Can someone from ez-robot tell when my warranty request will be processed?

Thanks, Calvin


Ez Robot have been closed since Dec 24th.... They just re-opened today... They should respond soon....

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@Alan, if you hadn't said anything I would have missed the fact my scorpion kit was missing the 2 rotation servos too. Thanks for the reminder.

@clovejr, they will respond, as Richard said, they have only just started back again after the holidays. Give it a few days/a week and if you still haven't heard chase it up. They are usually very good though so you shouldn't worry too much about it.


@Rich, your probably going to say no, but I thought I would offer... I can print you off your missing rotational servo parts and mail them to you... Just tell me what parts you need.... Consider it payment for all the help you have given me since I joined the EZ Robot forums....:)

Yes, I foolishly bought myself a 3D Printer.... ;)

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I did notice you bought yourself some 3d printers.

With all this stuff I'm sure I'll be fine:)

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(there's more that wouldn't fit on the table too!)

But thanks for the offer:)


No worries @Rich... If you ever need something printed, I don't mind.... Really...

That's an awesome collection... I actually printed myself a Six... Just need to order the servos for him....:) So let me answer a couple of questions, will you...:P

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I've let you answer loads lately (in fact I was awol for over a week until 2 days ago) You must be almost up to the 100 milestone by now:)


4 more dude!... Other than you and DJ, how many others do you know of who hit 100? I wouldn't mind being 3rd... :)

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I haven't really been keeping track lately (I haven't been keeping track of my own for months now), I'm sure DJ or someone else at EZ-Robot could look it up though (would be cool to have a scoreboard of sorts).


@Rich... thanks for the sabertooth ramping script by the way. Very timely... saves me to have to write my own...:) Ooops, sorry didn't mean to thread jack... To the Op, ez robot should respond soon. You don't need to worry about that...


Hello ,

To EZ-Robot ..... When will my warranty request be processed ?

I need a new H-Bridge to replaced the one that got fried from the factory wiring error.

Thanks, Calvin

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EZ-Robot customer services do not frequent the forum very often and do not deal with warranty claims within the forum.

Contact them using the Contact Us form and they will get back to you and process the warranty claim quickly should it be valid. I personally put in a warranty claim about a week ago and the replacement parts were shipped out Friday.

If you have contacted EZ-Robot previously and haven't received a response check your spam folders, there should always be an automatic response almost instantly. There is also be an automatic response once the ticket has been closed which asks for your feedback on the service given. If you don't have the first one then spam filters have caught it.

Drop them a(nother) message via the Contact Us page.


@clovejr I just sent you an message- but for some reason I did not receive the email you referenced here! The last email I have from you was on August 16th. Regardless- I can help you get this issue sorted. ;)


Hi Aislinn,

Thanks for the email that a new h-bridge is on the way. I would like to thanks everyone who has replied to this thread and especially to Dave Schulpius who verified my suspension that the h-bridge was fried.