Thank you for choosing Aerospace-Aviation360 for Part Number 5965770 described as Test Set, Fault Indication - Eng/Apu Generator. Tests Wire Integrity Of Eng And Apu Generator Wire Alerts. Mrb Requirement For Engine And Apu Change. by Mcdonnell Douglas. This is an ASAP Semiconductor owned and operated website. We are a leading supplier of aircraft tooling parts. You have 24/7 x 365 access to our diverse product database with the fastest lead times in the industry.