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Discussion Starter #1
Only recently noticed that when the bike is shut down, there is a very brief flash of the right-side indicators. While it's kind of charming in that "Herbie goes to Monte Carlo" way, wondering if this is an indication of an impending problem with the electronics--especially since Factory warranty is up in April... Anybody have experience with this? Is it some benign capacitor discharging, some hidden diagnostic gem, or nothing to worry about?
 

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it's the result of electrical noise kicking around in the electrical relay box (the one on the right side of the fuel tank with all the fuses in it). the electrical noise is the result of poor design. mv covertly wants you to be very happy your particular bit of noise doesn't affect operation of the blinkers while riding. it may or may not worsen or improve over time.
 

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the problem is the "brain service box relay" manufactured very poor by SAAB electronic
 

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Is poor build quality a known fact or just an assumption? If it's a poor design, was it specifically designed for MV? If so it was probably a joint design between MV and the manufacturer, or could also be an MV designed part manufactured by a third party. The manufacturer doesn't need to offer any design input if MV have supplied the specs and drawings.

It could also be simply a case of MV choosing an off the shelf product that is not fit for purpose? If the component in question is indeed manufactured by SAAB it may be that it was originally designed to be placed inside the passenger compartment of a car, or worst case scenario an engine bay. While an engine bay is indeed a harsh environment, it's nowehere near as harsh as being strapped to the outside of a bike.
 

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yeah there's no way to know who designed the circuit board inside the box in question. and the design of the circuit board is the problem (as opposed to it being a manufacturing problem). since the box is a flawed design, no amount of perfect manufacturing technique can correct it.
 

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Discussion Starter #9
I've never had cause to open one up and look at it, what's wrong with the circuit board design?
Yes, I too was unaware of a flaw with the board design... Is it caused by interelement capacitance--that would seem a plausible explanation...
 

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I've never had cause to open one up and look at it, what's wrong with the circuit board design?
well i have hooked a scope up to most of the wires connected to this circuit board, and many of them are loaded with noise. electrical noise must be held in check with proper bypass capacitors, or other circuit design techniques depending on the source of the noise. the fact that this circuit is loaded with noise indicates that it is poorly designed.

regardless, the fact is that about 1 in 4 brutale bikes have random electrical problems usually related to the fan, blinkers, and high/low beam headlights. the design of the circuit board is such that it takes low-level inputs (from the blinker-switch, high/low beam switch, etc.) and those low-level signals are amplified through several large solid-state relays on the circuit board to drive the fan, headlights, and blinkers. it's very easy to imagine some stray uncontrolled noise on the circuit board affecting the inputs of the solid state relays, especially during transient events on the bike (such as the fan turning on/off, the bike turning on/off, etc.).

it's impossible to prove that electrical noise is causing the problem without reverse-engineering the entire circuit board. but i've been involved in electrical engineering for about 20 years now and that's where i'd put my money.
 

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Auto electrics are inherently noisy, scoping external cables or I/O pins doesn't really tell you much as far as noise is concerned. There is no point in filtering/supressing noise externally as you'd still have to do it again at circuit component level.

Due to the harsh environment auto electrical components/products are normally fairly noise tolerant, and any filtering/suppresion components/cicuits are employed at the last minute (i.e. as close to the components/ciruits that may be potentially affected as possible). I could be wrong but it doesn't sound like that anybody has looked deep enough (at component level) into the problem to confirm or deny that noise is indeed an issue.

It seems for many owners reporting these types of problems that replacing the fuse/relay box fixes their problems. If the fuse/relay box was suseptable to noise via poor design then replacing the box would have little to no effect. So I'm not overly convinced that noise is a major problem. It stands to reason that if you take a component with a flawed design and replace it with another component with a flawed design then it won't fix the problem.

From what I can gather the majority of owners with these types of problems have claimed that their problems began shortly after the bike was wet either from washing or riding in the rain. Based on that, it suggests to me that in the majority of cases the problem is more likely related to fluid ingress/contamination (or possibly oxidisation) internally within the fuse/relay box rather than any form of influence from external noise.
 
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