Stereo buttons mixed

[matty88]

In our '02 Kia Carnival, we have the stock head unit. Sometimes when we push the off button, it mutes. We then try the mute button but then it does nothing. It only occurs on hot days, so I think it may have something to do with that.

[Car Audio Factory Outlet]

Dry solder joints on the PCB would be your cause.

This a common occurance with Asia and European built cars and if fact many japanese built cars as they can not handle the extreme heat generated in australia

You only have to look to the pulsars were you have common occurance of the dash instruments not all working eg. tacho etc they are a easy fix as you need to resolder any dry joints.

Same with your HU, also some of the major manufacturers have been cutting back the amount of silver in the solder which also causes this... especially stuff made in CHINA - e.g Alpine, as some of the cd ejecting issues are eith dry joints, the lacquer causes a short on the PCB or bridge... and dirty mechanisms.

Get 80% silver solder if you are going to do the job... you need to head the joint and reapply the silver solder... the best way is to use solder wick to get rid of the original and replace it with the good stuff.... also check all other joints.

[bezz]

wouldnt silver solder be overkill in this application? I havent had a problem with temperature using 60/40 solder on the PCBs I've worked with. More often than not these dodgy solder joints are more due to the solder not being applied properly in the first place as opposed to the solder itself.

[vy_storm]

Silver content is now being widely used as a replacement for lead based solders due to the ROHS compliance now being adapted worldwide (lead free is mainly SnAgCu). Due to the fact that the base materials are more expensive the solder has drastically increased price and asian manufacturers have been known to make cut backs and save on materials through various methods.

Having said that the problem you have might not even be related to silver usage as it may only be a simple tin/lead alloy in the unit. If they don't need to use silver then they won't.

[Car Audio Factory Outlet]

wouldnt silver solder be overkill in this application? I havent had a problem with temperature using 60/40 solder on the PCBs I've worked with. More often than not these dodgy solder joints are more due to the solder not being applied properly in the first place as opposed to the solder itself.

It is alright if you are living in Melbourne, but the pure heat of Queensland causes all sorts of issue with soldered units... especially traditional soldered components, no such a problem with board mounted components.

Even Home electronics cop the same issues... due to cost savings with the solder being used.

We see about 6 units a week come through here with dry solder joint issues... all are generally 12months - 3 years old.

True what you say with the solder joints, not being applied properly though more often than not it is heat enduced.

The other issue is the laquer.. which after some time exposed to heat can generate a bridge / short causing the same issue... also a common.

Have a look at a common problem with most Japanese made vehicles that are a few years old. They are having issues with instrument clusters, clocks and the like and they 99% due to dry joints.. take the pulsars common issue... tacho not working or half the lights in the cluster no working everyone that we have seen is dry joints. Honda is another with the clock cutting in and out.

And frankly the Japanese built vehicles are much better put together than the vehilces coming out of Korea, Malaysia etc.

[Tasmaniak]

but to be perfectly honest? go drop $100-150 on a HU and be done with it. Perhaps CAFO will have something.

[matty88]

I'm not going to anything about it, I just wanted to know what is wrong. Thanks anyways guys.