Pioneer DEQ-9200 audio processor with no power: corroded contacts cleaned and reflowed

At a glance

• Device: Pioneer DEQ-9200 DSP audio processor from a car audio system, posted with its controller, leads and microphone
• Fault: no power at all. It stopped powering up after being tested during a car audio installation.
• Cause: several corroded contacts inside, which is common on a unit of this age
• Fix: stripped the board down, cleaned the corroded contacts and reflowed the joints
• Result: powers up, the display, EQ graphic and controls all work, and sound passes through the inputs and outputs on the bench
• Cost to the owner: £60 in total (the £40 board-level assessment, then £20 for the repair), with tracked return postage

The fault

The DEQ-9200 is a dedicated digital sound processor and equaliser that sits between the head unit and the amplifiers in a car audio system. This one had been taken in for testing as part of an installation and wouldn't power up afterwards.

The owner booked our board-level repair assessment and posted the processor along with its controller, leads and microphone. Having the whole set made it possible to test the unit properly on the bench, rather than just checking for power.

What we found

With the board stripped down, the problem was easy to see. Several contacts inside had corroded. On electronics of this age that's common: years in a car mean heat, cold and damp, and contacts and joints suffer for it.

The fix

We cleaned the corroded contacts and reflowed the joints around them, so each one makes a solid connection again. No new parts were needed.

On the bench after the repair, with the EQ curve and presets showing.

The result

The processor now powers up, and the display, EQ graphic and controls all work. Powering up isn't the whole job on an audio processor, so we then tested the audio in and out on the bench to make sure sound was passing through properly. It was.

The repair came to £20 on top of the £40 assessment the owner had already paid, so £60 in total, and it carries our 90 day warranty on the work.

Questions about this fault

Can an old car audio processor like the DEQ-9200 be repaired? Often, yes. Many faults on units of this age come down to corroded contacts, tired joints or ageing parts, all of which can be repaired at component level.

Why would a car audio processor suddenly stop powering up? There are several possible causes. On this one it was corroded contacts inside, which can work for years and then stop making a good connection, especially once the unit has been moved, disconnected or reconnected.

Should I send the controller and leads too? It helps. With everything that connects to the unit we can test it the way it's used in the car, not just check that it powers on.

Got a dead car audio unit or other electronics?

Our board-level repair assessment is £40. We find out what has failed and give you a written price before any further work, and tracked return postage is included.