I recently had a battery drain completely on me and switched it out with a yellow top optima. Car ran fine but plugged in my sctx4 to read volts and running and driving was only around 11.9-12.4 volts at the most. Any ideas on what’s causing this?
A charged battery should read 12.6 or above. And when charging, You should get 13.7- 14.7 volts.
Have the FLAPS check the alternator while you check all the connections and cable ends. The cables can be corroded under the plastic insulation, so the voltage drop test is a good idea. @General karthief can you find the checklist or writeup on checking voltage drops?
No Crank checklist for 5.0 Mustangs Revised 24-Oct-2013 to update voltage drop figures. No crank, slow crank and stuck starter solenoid problems have the same root causes – low battery voltage and poor connections. For that reason, they are...