B737 FQIS problem
 

Hi guys, I've got a snag with a B737-300 and maybe some of you avionic guys can help.
The No2 FQI throws up ERR 9 when ever the A/C is climbing, when its level or descending nothing happens, and can never be reproduced on the ground. Its had several indicators and swaps, bussing plug cleaned, wiring agitated etc to no avail.
Anyone got any theories or clues?

I'm sure you've sumped the tanks. Maybe some tank diving is in order to look for lose hardware on the bottom of the tank, rolling around and touching the probe, or maybe a contract worker's body left in the tank since last overhaul.
Is this a Goodrich sys? What does the manual translate a "ERR 9" to?

'ERR 9' means indicator error, or loss of power to indicator. Sumps drained lots of times as well.

I guess I stepped in it. FQ problems with attitude change is usually crap in the tank, with water trapped around probes and lose hardware being the most likely trouble. Sometimes water has to be vacuumed out because sumping won’t get it. Since I wasn’t familiar with “ERR 9”, this was my first direction of troubleshooting.

Lose of power is a different type of problem. Bent pins in connectors, lose terminals, bad crimps, and even sheetmetal shavings on terminal strips and in wire bundles are things to look for. Does the gauge blank out, or does it just lodge the message? What brand gauges/system is it? I have access to BF Goodrich, Smiths and Simmons information in our line maintenance manuals, if applicable.

Is it a relatively new aircraft?

About 5 or 6 years old

mate, sounds like a classic wiring problem then. I suggest you do conn checks from the indicator downstream, and also disconnect everything downstream of the indicator and try the ole 1000V megger for a possible chaff to airframe. In the past I have seen many snags associated with airframe movement for a given attitude, the wings especially during climb.
good luck.

Hook up your test set, get a fat git to bounce up and down on the wing tip, it's worked for me a couple of times before!!

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It flew in, it'll fly out