Anybody ever repaired one of these things? Hans and Franz have figured out mine is fragged, as the car runs with an ECU from their 5-series sparts car but starts but will die under any load with my ECU.
They say they've seen this before with a 7 series of similar vintage and deduced somehow it was the airflow metering circuit.
Absent any bloack burned out parts I'm tempted to go down there, grab my ECU and resolder every joint.
Anybody played with these ever?
No, but similar vintage control boards are mainly discrete components and a common failure item is capacitors. If you're doing a home refurb of the ECU then you should replace all the caps and look for places where any have puked electrolyte onto the board. Then repair any tracks that have been damaged by the leaked electrolyte.
This probably isn't a job for your average Joe, but any electronics repair shop should be able to do it for $100 or so.
Very temperamental part.
I have worked on the 5-series ECUs from that era, and they are very, very prone to cold solder joints especially on the connector. Looks like it might be a wave soldering issue. Occasionally there are also some capacitor failures too, but a whole lot fewer than you'd expect. The 125'C rated caps from BCC seem good replacements when you do find a bad electrolytic, but most of the rail bypasses are mylars. Very nice design.
--scott
Thanks Scott. So I'm not out of my mind then that a good first order approsimation is look for and replace ant s*it that blowed up and resolder everything in sight.
Danke.
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