Skydat GX2 instrument failure

[Mc Guyver]

Hi all,

 

It would be interesting to know how many pilots have experience problems (and how often) with the Skydat GX2 showing open circuit on all the temps and the alarm light coming on.

 

The only way to rectify the problem is by switching the instruments off and then on again.

 

 

[Guest Crezzi]

Never had it occur on mine (approx 550 hours)

 

Cheers

 

John

 

 

[alf jessup]

Len,

 

I don't think it is a common problem, I only know of 1 person out of our group that had it happen to his trike only once and he turned it off and back on and no probs since.

 

Mine has done 630 hrs and had no probs.

 

Cheers

 

Alf

 

 

[Dieselten]

I have seen one that failed due to the 12 volts supply that is sent from the display unit to the engine module failing, it dropped to 1.32 volts and the entire unit failed to light up.

 

The failure was confirmed at the output of the main PCB of the dislay unit and the owner is currently working painstakingly through the components to try and localise the failure. There is a P-channel MOSFET, labelled Q4, which may be associated with this power-supply, but this is not yet confirmed. Both Source and Drain terminals have about 12.4 volts on them, the Gate terminal has 3.8 volts on it, which in theory should drive it to a very low forward resistance, so the equal voltages on Source and Drain tend to suggest the MOSFET is OK.

 

Working through a double-sided PCB without a circuit-diagram is not the best way to fault-find, but if the failed component can be found and replaced it may save the time and expense of sending the entire unit back to the manufacturer in South Africa. Anecdotally the turnaround time for a repair is about a month or more.

 

Not sure if there is anyone in Australia who is qualified to repair these units.

 

Postscript:

 

The problem was an open-circuit resistor, R1, a surface-mount 1-Ohm resistor which is immediately in series with the voltage regulator output. The resistor was replaced by a 1W 1-Ohm resistor with leads and the unit is now apparently "ops normal". Amptronics in South Africa emailed him the relevant portion of the circuit-diagram and were very helpful. I am told the most difficult part was removing the failed resistor due to its location and being coated with silicone sealant which stabilises a nearby toroid.

 

 

[Bluey]

I get one open circuit on average every 15 hrs or so.