Pz IV Inoperable
 

Guys,

I just took my Pz IV for a test drive and have a problem. For the first minute or so it was fine although it seemed to move slow. I drove it around, did some tunrs and even tested the airsoft gun and machine gun sound. When I hit the button to simulate firing the main gun I got nothing. Furthermore the tank became completely unresponsive. The lights were still on on the tank so it has power.

My first thought was "bad transmitter." So, I took a known good transmitter (same freq) and still nothing. I shut the tank and transmitter off and powered it up again and still nothing.

I tested the new PZ IV transmitter on my PZ III (same freq) and it worked. A quick look inside the tank revealed no obvious loose opr broken connections.

Has anyone ever experienced this with an HL?

RE: Pz IV Inoperable
 

This thread has some good trouble shooting tips! And did the sound out also, did you check the large resister?

http://www.rcuniverse.com/forum/m_7338336/tm.htm

The Blitz

RE: Pz IV Inoperable
 

Swap out the crystals with your spares. If that doesn't work, check the wiring but it's likely then the board.

RE: Pz IV Inoperable
 

Blow it out with your air compressor, rid of any loose bits that had gotten in there, check the big grey cap on the top of the board, it can sometimes jar loose, make sure its soldered well (and not just sitting there looking soldered), check the crystal in the tank for good contact, bend the pins outwards a little to guarantee good contact.

Other than that, very strange indeed

RE: Pz IV Inoperable
 

Well, I checked everything I can think of and still no go!! I have decided to send it back to Mato. HLs QC may be getting better but it is far from perfect. And please, no more about how Mato tests every tank before it leaves.

To be fair I have to say this is my 4th HL tank and the first one that has been a problem.

RE: Pz IV Inoperable
 

The one thing I did see you didn't try was changing the crystal in the tank(won't guarentee this is the problem).For myself with the crystal problems I have had it is always the RX crystal in the tank(receiver board crystal).Sounds like you have another tank you can pull a good crystal out of for testing the one that don't work.A set of crystals is a few dollars from Tower Hobby,sending your tank back to mato and waiting to get one back-????- BIGMIG [)][)][)]

RE: Pz IV Inoperable
 

I did swap out the crystals as well, just forgot to mention it I guess. I looked at the board and everything seems to be properly connected. I will let Mato fix it.

RE: Pz IV Inoperable
 

IMO you're wasting time and money sending the whole tank bank over a blown board. Drop in your spare and be done with it, ask Mato for a replacement under warranty or a credit for one on your next order.

RE: Pz IV Inoperable
 

Here is the latest boys. I emailed MATO about returning the tank and the were less than encouraging. The response was:

Thank you for your email. We are sorry to hear that about your tank. Under our return policy, it states that the customer must contact us within 3 days of recieveing the item if somthing is wrong. You recieved the item April 12, 2008. We recieved this e-mail April 21, 2008. We are sorry that the warranty has expired. We believe a new receiver board should solve the problem. Please see below link for the replacement receiver board.

http://www.matotoys.com/canada/produ...products_id=60

Again, we do apologize for this, but just like we place deadlines for warranty's on our customers, we also have to follow deadlines from our manufacturers.

Thank you for shopping at MATO TOYS.

Customer Service
Mato Toys International Inc.

So, be warned!! There is a 3 day warrantly on stuff you buy from MATO (What a bunch of BS!!!). Nothing says "I stand by what I sell" like a 3 day warranty.

Anyway, it dawned on me that I had a whole set of spare boards. So, I replaced the receiver board. This did not fix it. I then replaced the main board. It still does not work. I have replaced the crystal, tried multiple known good transmitters, and replaced the main and receiver boards with no affect.

It looks like I am stuck with a $170 worth of paper wieght until I buy more boards.


Everyone should decide for themselves which vendors they wish to use. Just be aware that the MATO warranty is only three days. Also, remember with the Heng Longs you always run a risk of getting junk.

RE: Pz IV Inoperable
 

Might be a dumb question, but are your batts OK? Can you test there volts at all? or even swap it for a known good charged one?
Also swapping crystals, are you putting in FM ones, not AM?

Yours Simon M.

RE: Pz IV Inoperable
 

Thanks Simon, I did try know good batteries and crystals.

RE: Pz IV Inoperable
 

Just a couple of things what ever they are worth.Three day warrenty for replacement is kind of standard practice with a lot of dealers as far as that part goes.(can get shafted here if its a gift and not used and tested in that time frame).
Second part you are saying just don't make sense.You have a known working "radio"You are using known working "set of crystals"and you have replaced the board (but was the replacement board "FAULTY").If the radio is working,the lights on the tank are flashing when you turn it on(means its getting power to the main big board)but thats itIt has to be the radio and receiver are not communicating with each other,or the wire connector from the small board to the big board is not connected or working right and not sending any commands to the big board.Sometimes just replacing a board don't work because the board you used is also bad.Something here is being over-looked-???? Question is what???? BIGMIG [)][)][)]

RE: Pz IV Inoperable
 

BigMig,

The very first thing I tried was a different crystal. I knew this crystal to be good because I used it in another tank only moments before trying it. The next option was a different transmitter (controller). This was also confirmed to be good before I tried it. I then looked everything over and all the wires seemed to be firmly in place. So, I contacted MATO and the sugegsted replacing the receiver board. Of course they wanted me to buy one but I had one that I took out of a HL Tiger. It worked when I took it out about a year ago but beyond that I don't know. THe same can be said for the main board. T.hese boards may be faulty, but I think it is at least a little bit unlikely.

It is all very suspicious. As I initially mentioned. It worked fine until I pressed the machine button on the controller. After that I got nothing but blinking lights. I agree with you that something is being missed. I don't really have a lot of expertise when it comes to electronics so I think I may just put El-Mod guts in it and be done with it. From what I understand El-Mod is pretty easy to install.

RE: Pz IV Inoperable
 

El Mod is not a stand alone system. You'll still need to use HL or aftermarket controllers.

These are $100 tanks. They are not UL compliant or follow all the safety rules that our government forces companies to do. All that gets you an $800 Tamiya tank. If you accept that these are not the most reliable and carry spares for each one you're tanking experience will be a pleasant one.

In the 2 1/2 years since I entered the hobby I've bought and sold over 20 tanks and have just as many blown boards. Some were faulty, even brand new, most failed because of something I did. My posts regarding failed boards concentrated on trouble shooting and trying to replace the parts. In the end, it still isn't worth fixing them. For $100 I don't expect the seller to warranty the item either even though several did voluntarily when I mentioned quailty issues.

Mr. Heng Long wanted to drop the tank line and concentrate on his gas/nitro trucks. If enough people complain I think that instead of developing/producing more reliable equipment and raising the prices, he might just discontinue tanks altogether. Just my .25 cents worth! :D

RE: Pz IV Inoperable
 

Hey Swath,

I agree with most of what you say. You are right, it is a $100 tank. I guess I am overly frustrated because the electronics is something sort of foriegn to me. All I ask is that it work as advertised. I am gonna look at it again tomorrow and see if I can figure it out.

RE: Pz IV Inoperable
 

Believe me I know it can be frustrating. The receiver boards aren't usually the problem, I've never had a problem with mine. It's always the main board. In the beginning we kept reattaching the wire from teh on/off switch to the receiver board and they kept blowing, the big gray transistor would get hot and you'd hear all the motor transistors pop pop pop pop! Now we leave that wire off, even on new tanks.

Start over and connect one item at a time and test by turning it on. Don't even put it back in the tank, just do it on the table.

RE: Pz IV Inoperable
 

Will a company take a defective tank back if you have opened up the tank?

RE: Pz IV Inoperable
 

IF they know about then no. If you have replaced everything out (boards, transmitters etc) and its still no working, then you're either doing something very wrong (Flat battery etc) or your power switch is stuffed. Do the boards work out of the tank?

RE: Pz IV Inoperable
 

Swathdivers theory on spare boards is a sound one. The cost of mailing these tanks great distances for return or repair is impractical, regardless of what retailer you are dealing with. Next time you order a tank, buy a couple of extra boards.

Lets not fool ourselves boys. You can't ship big tanks through the postal service everytime you have a problem with them. It costs too much. This is very much a DIY hobby. You must roll up your sleeves and fix what needs to be fixed. The parts are available, so like the slogan says, " just do it"

You don't need to be an electrical engineer, but you need to learn how to solder. I sympathize with you guys who have problems and everyone here will offer all the help and encouragement they can, but you must face the reality of this. If you don't I promise you, you will be disappointed. This is what makes it a hobby. I don't care if it is a $100 Heng Long or an $800 Tamiya. You have to learn to fix and repair these and have fun doing it.

I am not aiming these remarks at anyone, I am just pointing out the reality of what RC tanking is. You must learn and repair things that get broken, and you must enjoy doing it. It is the hobby

Again I make these remarks not to offend anyone, but just to point out the reality of 1/16 scale tanking.

I have been in this hobby for just over a year, and the help on this board has been outstanding. There is nothing on a Heng long tank I haven't touched, fixed and improved. This has been possible because of the great help here and my desire to "own" these things. There is nothing I can't fix on a Heng Long, and I encourage others to have the same attitude. Parts and upgrade pieces are available at a very reasonable cost. So enjoy the challenges and opportunties to improve your modeling, and electrical troubleshooting skills. We have all been there, and had to endure the same. It is what makes us Brothers in Arms!!!!!!!

Now Lanierrl. Get that freaking tank running. Otherwise I am going to start calling you sailor boy!!!!!:D

RE: Pz IV Inoperable
 

I think the problem might be that of the communications cable btw the reciever board and the main board, somehow there maybe an internal breakage of the wire. try to use a new one or use an ohm meter to test the wire if there are breakages.

RE: Pz IV Inoperable
 

THIS IS NOT AIMED AT ANYONE

I must admit that YHR's comments are true, part of the reason for any of the RC models (as opposed to RC toys) are popular is the 'engineer' in us all. Planes, Boats, Cars, even robotics requires a certain amount of electro-mechanical (I think the popular name for it now is mechatronics) skill, or willingness to acquire.
It is getting easier, I can remember when in the UK you needed a radio ham licence just to fly your RC plane!


Yours Simon M.

RE: Pz IV Inoperable
 

Hi lets have a look at your original symptoms

At first look, I would diagnose a duff battery. That has been swapped over you say and no change. Have you put the Pz IV batt in to the Pz III ?
You seemed to of checked out the TX to be OK.
Based on all that I have read, I would diagnose that one or all of the following components, Q11, D1, IC3 has died on the TK-RX13# board. Since I don't expect you to repair to component level, change TK-RX13#. Keep it for the transistors on the heat sink, and IC1, as these are the normal ones to fail.

Yours Simon M.

RE: Pz IV Inoperable
 

I noticed BigMig touched on this as well.

You might be onto something here. Try another 3 wire cable that connects the Receiver to the ESC. I've installed a pile of Darkiths DBC's. They basically sit between the receiver and the ESC. I had an issue or two with the first DBC's I built.(My screw ups), and when I did my tank responded exactly like lanierrl's.

So replace the 3 wire cable, if that doesn't work flip the board and then resolder the three pins to the socket. Maybe one of them is loose and the connection cracked.

Reverse engineering this, if this condition exists, then your tank would behave exactly as it is now, so I think this is a sound path to take in order to fix it.

:DOh, I don't mean ot be rude but there is a start button that needs to be pushed!!!!! Sorry, but hey forgetting to do this would also cause you this problem, so I got to mention it:D

RE: Pz IV Inoperable
 

Thanks to everyone who has contributed in helping me solve this mystery!!! I am thankful!!

You crack me up YHR!!! [sm=tongue_smile.gif]

Believe me, I was so convinced I was doing something stupid I took out the instruction book and went through it step by step. I took out a magnifying glass and eyeballed every connection for something suspicious. I will try switching the cable as you suggest. I will be pissed at myself if that is the fix. [:'(] That would have been a lot easier to check than all the stuff I have done.

I did notice one thing last night before I went to bed. At the front of the tank the wires that go to the headlights are pinched between the two halves of the hull. It looks like this was on purpose and one of the wires has a small patch of bare wire showing. I looked and it does not lok like it is coming in contact with any other metal but I think I may fix that just in case.

samarkh,

I did test the battery in the Pz III and I have already chenged out the TK-RX13#.

RE: Pz IV Inoperable
 

For whatever it's worth. I would suggest touching up the solder joints with a bit of fresh solder. Sometimes you may get one or more "cold" solder joints which may cause this type of problem. I've had experience, where the solder joint looks good externaly but is not making full or no contact.