Flickering xenon again

[mikeloadsasaabs]

Back about 18 months ago, perhaps a little more, I was having trouble with one of my xenon bulbs flickering. I eventually replaced both bulbs at vast cost, but over the last few weeks the bulb in the same lamp has started flickering. I'm thinking perhaps the control unit is dodgy. It seems odd that the first bulb lasted 10 years before the problem started, yet it's come back after only c.18 months. It looks like the control unit is one of these:

http://www.skandix.de/en/spare-parts/electrics/lights/headlights/control-unit-gas-discharge-lamp/1051704/

Anyone else had the problem? It's tempting to take the cheap option and just buy another bulb, it might be cheaper to keep replacing them over the expected future life of the car than buy a new control unit!  Doesn't seem worth taking the risk of buying a second-hand unit, unless failure is extremely rare, as I might just get the same problem again.

[Audax]

Given the age/mileage of your car and the symptoms I'd guess a control unit is a likely fault, however you're supposed to calibrate them with Tech-2 when you replace them. Although, what is the brand of bulb that failed? Some of the cheap ones don't last very long.

[mikeloadsasaabs]

Osram, chosen because they are less likely to be cheap copies, and bought from Autobulbs Direct.

Is it a common failure? It's not something I remember anyone mentioning here before, although to be fair we are only a small subset of Saab owners!

[Audax]

Is it a common failure?

It's a common enough failure that I can say I've replaced a few myself in the past but never put them into stock. I think it has been mentioned here before.

[GeoffW]

Audax - can you clarify what the calibration covers ?
I've replaced a control unit in the past (with a second hand one) and am interested in making sure I've done the right things after replacement (I checked and adjusted my beam as mentioned below).
From earlier posts, I had the impression it was solely tied to the levelling mechanism and could be done instead by adjusting the beam manually with the adjustment screw accessible from the top of the car alongside the headlamp in question.

[mikeloadsasaabs]

Another question for you Audax - would you be inclined to replace the control unit with a new item, or risk second hand?

[Audax]

For calibration I'm not entirely sure what it does, I think it just sets the default value for what is considered "level" I'm not sure if it does anything else on top of that and maybe adjusting the lights with a screwdriver is OK.

As for using a second hand module I'm really not sure, €150 for a new unit sounds pretty cheap but if you can get a second hand unit for not much money and are willing to fiddle about and DIY the job it might be a cheap way of getting it working on an older car.

[mikeloadsasaabs]

Decided to go for the new unit at €149 - not genuine Saab, but at least new. The Saab genuine was €225. I also discovered in my searches that the same unit is fitted to a number of other cars, including the Audi A4 and Renault Laguna. There were a few on Ebay around the same price, some new, some used, but decided to go for the known quantity.