Old to New RX18

[ToXic U4ia]

I bought a new Henglong Panzer III from Banggood.
It has the older RX18 installed (from 2015) where you have to move left stick up to fire and the Air Soft has an on/off switch.
I installed a new RX18 and new style transmitter.
In the 8 pin connector I had to reverse the elevation and traverse
wires.(the red & black, blue & yellow)
Now the stick movements are correct.
My problem is the Main Gun, Air Soft unit, will not fire or make the shooting sound. If I turn off the
Air Soft switch the turret will do nothing.
I reversed the green and brown wires and the gun will not stop elevating and fires repeatedly
with out any sound.

Any ideas?

[HERMAN BIX]

I had the same issue with retrofitting one of these sets into my RX18 style King Tiger.
Never got it resolved Im afraid.

[wibblywobbly]

The airsoft and shooting sound requires the airsoft unit to move, and to activate the microswitch. To test it push the two contacts on the microswitch together when firing the gun, or bridge the contacts with a piece of wire.

The new circuit still goes through the two right hand pins on CN3. To make the airsoft work, you need to find out which pair of wires on the 8 pin connector generate a pulse when the gun is fired. You may need the new style upper hull connector, and switch any changes made on the 8 pin back to standard.

What they have effectively done is got forwards and backwards on the elevation by using the turret rotation circuit. The shooting is activated by pressing the right hand button on the tx when the elevation stick is up. This button sends the fire pulse to the airsoft, so it must be a shared circuit. My guess is something to do with pins 2 and 5 on the 8 pin, on the new board.

Edit:
Just checked pins 2 & 5 on the 8 pin. When the left stick is pushed up, while the left button is held down, there is a 7v pulse on the circuit. This is probably the airsoft trigger.

One other thing to bear in mind is that the 5 pin plug on CN3 must be inserted as this completes the circuit from the microswitch.
If you wanted to remove airsoft, you could snip the two right hand wires on CN3 and twist them together. This tricks the RX18 into thinking that the airsoft has activated the microswitch and will give you the firing sound and the track recoil when the gun is fired.