general electronics help

[waggs]

ive got a general electronics background but keep getting stuck trying to fault things,, example , my car stereo packed up after some water leaked onto it from a heater leak,, its a 2year old pioneer DEH1530R cd radio,, i power it up but the unit is totally dead , no display , ive traced the power through the unit to a IC with which is attached to a large heatsink on the back of the unit,, not sure what to do next,, the unit shows no sign of water damage or burning etc, it looks like new inside,,

could anyone help me fault it, id like to find the fault rather than throw it away,, if its a componant that cannot be replaced then obviously i will throw it,, any help appreciated,,

alex

[Pentode]

One big problem is that water can get every and anywhere... more so under any components which can be a 'pain' if they are surface mounted - components that don't have leads.

One thing to look out for is tell tale signs of water marks or corroded pcb tracks. Another popular trick is to corrode the plated through holes if it's a double sided pcb or printer wiring board.

Any dampness can also cause leakage between the copper tracks and IC pins, an inspection under a magnifier glass should proved the above clues, sometimes a little warm air 'not hot' for a minute or so.... from an hairdryer may help

davy