TC reported APS intermittent fault indication. ~~~~~ 1657-A/c #2 isolated. Checked TIMS FC 404 & 414. Checked U / V / W cables found insulation test for A/c 2-1 Fail. A/c 2-2-Pass.  Isolated & Tag out A/c 2-1 U / V / W cables. Normalised A/c #2- Able to Cut In/Out. Monitor for 1 hr-Ok. Cab was cooling. Raise Noti to RSW for CCU servicing.     Ethan / Sridhar.  13.05.2023. Noti to RSW- 2488359.