| of the problem where there is no communication from the ECU consult port. Other ECUs will work fine. I was able to take a look at an ECU that had this problem and I did some pretty extensive troubleshooting to see if the problem was repairable. Here are notes I made from tracing the circuit out.===========Z32 ECU Consult troubleshooting notes============Micro HD63C03YCPView with ECU Harness Connector facing right.
Tx- P24 (micro pin 14) to R875 (left side) then (right side) to Q872 Base then Collector to R873 (left side) then (right side) to Q871 Base then Collector to R871 (top) then (bottom) to ECU pin 22.
Rx- P23 (micro pin 13) to Q851 Collector then Base to R852 (left side) then (right side) to D852 to ECU Pin 21.
Clock- P22 (micro pin 12) to R864 (right side) to Q861 Collector then Base to bottom of board via feed through to R862 left then R862 right to D862 top then D862 bottom back to top of board via feed through then ECU pin 31.==================================================== Unfortunately I was unable to repair the problem. All traces between the components had good continuity. All components that made up the circuit were good. Everything looked normal and I compared everything to a good working ECU. I can only assume that there must be a problem internal to the micro itself. Here is a picture I put together from the PDF on the specs for the ECU micro showing the serial pins to the micro. 
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FYI. Some of you may have this problem or have heard - 
