1、Lessons Learned Entry: 0505Lesson Info:a71 Lesson Number: 0505a71 Lesson Date: 1994-07-12a71 Submitting Organization: LARCa71 Submitted by: Bernard LewisSubject: Failure in a CPU Consisting of Two Boards could be due to Oxidation on the Connecting Pins Description of Driving Event: N/ALesson(s) Lear
2、ned: When a failure occurs in a CPU consisting of two boards, connected by pins to form one unit, failure could simply be due to oxidation on the connecting pins. In many cases, disassembly, or merely, flexing the board, will correct the error. Moving the pins, either by flexing or disassembly, remo
3、ves the oxidation.Recommendation(s): Backup limit switches are in use on each device that exceeded movement limits. The watch dog timer will shut down sequencer “C if proper operation is not achieved within the first few seconds after start up. These two actions will prevent damage if there is a fut
4、ure sequencer failure.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/AAdditional Key Phrase(s): a71 Computersa71 HardwareAdditional Info: Approval Info: a71 Approval Date: 1997-04-02a71 Approval Name: Elijah C. Kenta71 Approval Organization: 421a71 Approval Phone Number: 757-864-3345Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
