GTN 750 Xi fan failure

[Watzlavick]

Yesterday when returning home from a day trip, I noticed the fan in my GTN 750 Xi running way faster than normal at startup. It was 90 deg F outside and I'm used to it running at high speed when it's warm outside but this time it kicked into turbo screaming mode. I started up and soon after got a "The cooling fan has failed" message. I was on an IFR flight plan so I didn't want to reboot it in flight. Sometime during the flight it must have fixed itself because the message went away. After landing, I cycled power on it and the fan turned on with the sound I normally hear. Could a flaky tach wire to the fan cause this behavior? It has about 50 flight hours on it plus a bunch of ground time.

 

[larrynew]

I replaced the fan on my 650Xi two years ago. Very easy and cheap. I think I spent $100 and it took about 20 minutes.

 

[Walt]

Don't forget to check the connections (pins and connector).
Unusual as I very rarely/almost never hear of a failure.

 

[KeithB]

Don't forget to check the connections (pins and connector).
Unusual as I very rarely/almost never hear of a failure.

Especially tiny wires on the fan connector (molex connector to dsub) - difficult to strip, and need a different setting on the crimper - maybe 24/26 gauge?

 

[dmattmul]

Anyone installing a GTN (750 or 650) make sure you can access the rear of the stack!