Mojave Strange Problem Brand New Mojave

[Topdeck07]

Hello everyone,

Hate to introduce myself this way, but I am having a very frustrating issue. My son wanted to get into RC cars, and well I thought it would be pretty fun to go back into the hobby after many many years. So, today I went down to the LHS and bought 2 Mojave 6s' , Spektrum dual charger etc. I got both of them unboxed and bound after charging the batteries (single 6s) and took them outside.

My son's car ran for about 5-6 minutes and then just became unresponsive. I turned both the vehicle and the Tx off and restarted. The ESC no longer makes any startup noises. However, if I turn the truck on before I turn the Tx on, it will make the noises. When the Tx is then turned on, the fan goes down to a very slow rate and there is no response to any inputs on the Tx. No lights blink on the ESC.

To clear up future questions here is a list of considerations:

• The truck will make startup noises (chimes?) only when started with the Tx off
• When the Tx is turned on, the truck "dies", i.e. fan on ESC slows way down and truck is not responsive
• When the truck dies, no lights blink or are solid on the ESC. The only light on is the receiver
• Light on the receiver turns on and off when the Tx is turned on or off (it sees the Tx)
• I swapped the battery for the battery in my truck and still doesn't work
• I swapped my son's battery into my truck and the truck turned on and functioned as normal, i.e. battery seems fine
• I tried rebinding the Tx and that didn't work
• I tried resetting the ESC to stock and that didn't work
• The Tx had brand new batteries in it, swapped them for another brand new set, nothing
• Vehicle was driven with the throttle limiter at 50%, tried starting with other configs, nothing
• Throttle trim is at zero
• Dry conditions, driven on short grass and pavement. There is no lose grass or anything binding the fan and everything is bone dry

Any ideas?

Thank you in advance!

 

[Doom!]

Welcome to the group, I don't have an answer for you but I'm sure someone will be along shortly who can get you all sorted out. Hope it's an easy solution, the Mojave is a fun beast!

 

[Cheez]

Yours works, his doesn’t.... take his back to LHS and get one that works

 

[Exc3l]

Seems like when the tx gets bound to the RX it takes a lot more power? Seems like the ESC or the radio gear...

 

[Cheez]

It’s a moot point.... brand new does not work take it back

 

[Topdeck07]

UPDATE:

Somehow I got the truck to stay on while the Tx was connected and the throttle will work, but if I try to touch the steering the fan slows down and truck resets by playing the startup noises again and will do that over and over again as long as you touch the steering wheel after start.

• Truck will stay on with Tx on
• Throttle works
• Steering input causes the ESC to reset
• Unplugged servo from Rx and no restarts, and throttle still works

Thinking fried servo?

It’s a moot point.... brand new does not work take it back

Yeah, that is where I am at. Normally I try to solve stuff like this because I have come to distrust any company's customer service but I refuse to pay $650 for this truck and have it break almost instantly.

 

[Greengaunja]

Yeah, I would say it's ESC. HORIZON customer service told me it's hit or miss with them. The ESC in a brand new ECX Amp for my son failed and a brand new BLX 100 failed on me. Fast replacements in both cases. I will give Horizon this much, they stand by their products. If your LHS has another, it could be a quick exchange for you. They should deal with Horizon themselves.

UPDATE:

Somehow I got the truck to stay on while the Tx was connected and the throttle will work, but if I try to touch the steering the fan slows down and truck resets by playing the startup noises again and will do that over and over again as long as you touch the steering wheel after start.

• Truck will stay on with Tx on
• Throttle works
• Steering input causes the ESC to reset
• Unplugged servo from Rx and no restarts, and throttle still works

Thinking fried servo?


Yeah, that is where I am at. Normally I try to solve stuff like this because I have come to distrust any company's customer service but I refuse to pay $650 for this truck and have it break almost instantly.

I was the same. I'm used to arguing with them. Horizon surprised me though. Twice

 

[jkflow]

My guess is a bad servo, seen many posts lately with this symptom and almost new trucks. Take it back and they will probably give you a new servo in the shop. Definitely a warranty case but better than waiting a couple weeks for shipping etc.
Could be a bad ESC or some wiring issue as well but you have to swap items to find out.

 

[Engineer]

My thought would be a bad servo as well. Unplug the steering servo and see if you can get throttle response back.

 

[SrC]

@jkflow , you beat me to the punch again. The servo first....
Take it back to your LHS ASAP. If you get a hard way to go or the LHS wants to send your stuff to HH, you can just bypass him and call HH direct. But any decent LHS will have Arrma parts and fix your issue inside of an hour. Should be bashing 2 hours later. IMHO. I would even first ask for a new Mojave that works if LHS has one.
There was another thread here recently with a Servo causing the same issue. It was defective and destroying the BEC output. ESC Fan would bog down. Same . Seems that Spektrum S652 servo is a problem for many. Not a unique issue at all.
I believe Arrma has a 30 day full refund policy from authorized Arrma dealers. FWIW. Hope the LHS would honor that.

 

[Topdeck07]

@jkflow , you beat me to the punch again. The servo first....
Take it back to your LHS ASAP. If you get a hard way to go or the LHS wants to send your stuff to HH, you can just bypass him and call HH direct. But any decent LHS will have Arrma parts and fix your issue inside of an hour. Should be bashing 2 hours later. IMHO. I would even first ask for a new Mojave that works if LHS has one.
There was another thread here recently with a Servo causing the same issue. It was defective and destroying the BEC output. ESC Fan would bog down. Same . Seems that Spektrum S652 servo is a problem for many. Not a unique issue at all.
I believe Arrma has a 30 day full refund policy from authorized Arrma dealers. FWIW. Hope the LHS would honor that.

Yeah, that is what I am thinking. We are going to walk it right back into the LHS tomorrow and see what they say. Hopefully, we can get everything resolved tomorrow. I will report back with the results.

Thanks, everyone for the responses!

 

[SrC]

Good luck. Enjoy.
Be safe.

 

[Gato]

yup, servo. Same happened to my Kraton 6s. unplug the servo and try again. Mine made it about 15 minutes before releasing the magic smoke, then same symptoms you describe.

I went through HH to replace mine, but i aslo ordered a 35kg amazon special. still waiting (almost 3 weeks now) on the replacement, but the amazon servo is doing great

 

[Topdeck07]

Update:

We opened a warranty ticket with Horizon and they are working on finding a better long(er) term servo solution for us. In the meantime, we took the truck back to the LHS and they hooked us up with a new servo to get my son up and running in the meantime. We ran the trucks when he got home with no issue!

 

[jkflow]

Glad you got it sorted out.
Enjoy the heck out of them.

 

[Cheez]

There ya go

 

[jrm850]

Saw this last night and figured it was servo too. Funny thing, my "used" one time use Mohave by previous owner had a seized up servo as well.

 

[jkflow]

Just based on many posts, there seems to be a bad batch of servos. They will sort it out eventually, they can't stay in business with these frequent failures.

 

[Tony Slade]

Just purchased a Brand New Kraton. My steering doesn’t work at all Throttle works but that’s it. Will take back to the Model Shop as soon as it opens

 

[Exc3l]

Did you try a new servo? If the servo is shot warranty a new one.