Cirrus Bolster Switch panel (PN A1850)

I have an intermittent BAT2 switch on my Bolster switch panel (PN A1850), 18554-020 in Cirrus Illustrated Parts Catalog. Cirrus does’t make the panel nor offers a fix for this. Moritz which made the panel was bought by Radiant which doesn’t have drawings to make repairs. I’v tried using deoxit 5 contact cleaner as noted on previous threads but still doesn’t work. Apparently there’s over 200 airplanes with this switch panel. I haven’t been able to find one online or at salvage shops. If anyone has a suggestion for a repair, it would be appreciated. Thank you.

Hi William, what year/model is your Cirrus. I have a similar problem on a 2003 SR22, but a couple of switches down the line.

The bolster panel switches can fail by having bad/no contact that gets fixed with contact cleaner, but they can also fail mechanically or by a welded/destroyed contact. Deep-dive disassembly of the panel allows them to be replaced, actually without any soldering. They are mounted with 1/4" quick-disconnect terminals. This is the basic switch.

The white indicator dot on the rocker seems to be a special Cirrus addition and is just a stick-on decal. Moving it from a bad switch to a new Mouser switch probably could be done after minimal coffee intake.
It’s possible to remove the rocker from the switch assembly. There are two springs and two contact bars that might go flying if you don’t hold your tongue right. If a contact bar has welded itself in place, the rocker, with the dot, could be used on a new basic switch like above. This whole procedure could be done with only having the bolster panel removed from the plane, but reassembly of the switch guts is tedious at a minimum.
As far as the legality of any of the above, I guess it’s between you, your AP/IA, and God. A discussion about grounding, permanently, an airplane over unavailable parts or repair manuals (even from the manufacturer) is probably in order.

1 Like

Thank you for providing a part number for that switch. I spent 30 minutes looking though digikey and mouser, without success.

All my switches work but I know that sooner or later, one will fail.

The FAA is ok with replacing standardized electrical parts with equivalent parts (same specs, same dimensions). An avionics shop could do it or an independent mechanic. Don’t ask a cirrus service center - they can’t do it.


I believe the word you were looking for is won’t.


1 Like

Here is a swtich that I have not found except on early bolster switch assemblies. Note the pin insertion contact verses the blade type contact.

Probably in here somewhere. Mounted in a PCB? Pic of top?