2002 Sebring. New battery but after driving car for a while battery dies.

poetman1500

2002Crysler sebring new battery drive car for a while car dies battery voltage low around 10 volts Checked alt at hi Idle was 14.1 volts my friend says ecm is bad as that is where the voltage regulator is

thecardoc3

The voltage regulator is inside the PCM, but failure of the field circuit that the PCM is controlling is common and needs to be checked before you just jump on a PCM replacement. The dark green/orange wire brings 12v power to the alternator brush assembly fro fuse 25 (20 map) in the power distribution center and the dark green wire goes to the PCM pin 8 of C1. The PCM duty cycles the ground to control the field strength of the alternator rotor and that controls the alternator output voltage.

With a scan tool you should first check for codes, and then you can go to the ASM tests (bi-directional controls) and command the PCM to control that field circuit and then you can test it for any issues without the engine running.

ray80

What is alt voltage at regular /warm idle?

poetman1500

The voltage that I measured was 14.1 at idle but the car was not fully warmed up yet

thecardoc3

Put your voltmeter on the AC scale and measure the voltage that it shows at the battery with the headlights and rear defogger on.