Panzer IV electronics Heng Long

[Condor505]

I recently bought a Heng Long Panzer IV minus it's transmitter for the princely sum of £10.00 needing a bit of T.L.C. It's the 27mhz infrared short barreled version in Panzer Grey. So I repaired the tracks then I fitted matching crystals to the tank and my transmitter from my Heng Long 27mhz Tiger 1. So I switched on and it all seemed to work fine for a while. Then it stopped working and only the engine sound worked and no response to the transmitter. Any advice would be most welcome.
Also if any one has instructions for this tank I would really appreciate a copy so I can see where the details are fitted.
Thanks

[HERMAN BIX]

Though it may seem odd, check the main battery charge in the tank.
Check the contact of the new crystals as they can loosen for no reason.

[Son of a gun-ner]

Had you turned everything off, then came back to it, or did it all just stop responding mid play?
Was the red light on the transmitter still glowing, indicating it was on, and still had power?

[Herr Dr. Professor]

Whenever this happens, I take out a different, better MiMH battery, fully charge it, and put it in the tank. The procedure has never failed me. Then I chuck the original battery. I have also updated all the crystal electronics to newer.

[Condor505]

Thanks all for the advice. I'll try the various fixes and get back to you all.

[jarndice]

The older Heng Longs Tanks --Pre Digital had a specific way of starting them,
I cannot remember whether it was tank on first then transmitter or transmitter on first then the tank on,
Either way if it was the wrong way round it would not start.

[Condor505]

I think I've narrowed the problem to a dud crystal. So I'm going to get a new set. It also looks like it may have been used in wet conditions. I'm going to have a look inside when I get the chance. Also I'm still on the lookout for a instruction book for this particular tank. even a photo copy would be good.

[Condor505]

Just received a set of crystals today. Inserted them in the right places, switched on all looking good fired her up engine started lights stop flashing gun up and down okay, turret traverse left right okay, forward motion slight jerk then nothing. No movement at all and no traverse or gun up and down. Left light flashes, right light flashes dimly. Sound effects work normally. Well it looks like I'm going to have to open her up. Any advice on what to check and upgrading the electronics would be welcome.

[Meter rat]

Battery not holding charge. If the battery is old then before you rip it apart, try a new/different battery..