1) Discussion with client:
-To get pertinent data of issues
-Have any previous repairs been performed?
-Has car been driven on too many short trips?
-Have the doors been left open for too long e.g. at a car wash or stereo shop?
2) Visual Inspection:
-Have any previous repairs been performed?
-Are there any aftermarket electronic components installed?
3) What is the age and condition of the battery and the battery terminals?
-Run Midtronics electrical system analyzer for Battery state of charge, Percent of health and CCA.
-On newer cars check the IBS (Intelligent battery sensor) and BST (Battery safety terminal). Torque of IBS negative cable nut is critical (5 Nm or 44 In/lbs.).
-Check for any corrosion and acid leakage on the terminals and cables. Check for cleanliness and tightness of the terminals and cables.
4) What is the condition of the charging system?
-Run Midtronics electrical system analyzer for alternator output and A/C ripple.
5) Utilize inductive meter to check for excessive battery drain.
-Make sure vehicle goes to sleep, remember to latch doors and lids, desired ~25ma.
6) Is the charging system voltage getting to the battery?
-Run voltage drop test from alternator to the battery. Maximum desired is .400mv.
7) Run controller interrogation with scan tool for energy diagnosis.
-Print results, check for any faults in the DME for the BSD or IBS, Check TSB’s.