Symptom Chart

WARNING: This page is about a different car, the 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM CHART

Condition	Possible Sources	Action
The charging system warning indicator is on with the engine running (the charging system voltage does not increase)	I circuit 1183 or 1185 B+ circuit fusible links B+ circuit 36 Upper generator Lower generator Powertrain control module (PCM)	GO to PINPOINT TEST I .
The charging system warning indicator is off with the ignition switch in the RUN position and the engine off	Upper generator connector C102a unplugged Lower generator connector C1251 unplugged I circuit 1183 or 1185 Lamp circuit 904 Upper generator Lower generator Instrument cluster Powertrain control module (PCM)	GO to PINPOINT TEST J .
The charging system warning indicator is ON with the engine running and the battery increases voltage	Lamp circuit 904 Instrument cluster A circuit 35 I circuit 1183 or 1185 Upper generator Lower generator Powertrain control module (PCM)	GO to PINPOINT TEST K .
The charging system warning indicator operates correctly but the battery voltage does not increase	B+ circuit fusible links B+ circuit 36 Upper generator Lower generator Loose or damaged harness connectors	GO to PINPOINT TEST L .
The battery is discharged or battery voltage is low	High key-off loads Upper generator connector C102a unplugged Lower generator connector C125la unplugged B+ circuit fusible links B+ circuit 36 A circuit 35 I circuit 1183 or 1185 Upper generator Lower generator	GO to PINPOINT TEST M .
The charging system warning indicator flickers or is intermittent	Upper generator connector C102a unplugged Lower generator connector C125la unplugged I circuit 1183 or 1185 Lamp circuit 904 Upper generator Lower generator Instrument cluster Powertrain control module (PCM)	GO to PINPOINT TEST N .
The charging system overcharges (battery voltage is greater than 15.5 volts)	A circuit fuse A circuit 35 Upper generator Lower generator	GO to PINPOINT TEST O .
Battery leakage or damage	Battery A circuit 35 Upper generator Lower generator	GO to PINPOINT TEST P .
The voltage gauge reads high or low	Upper generator Lower generator Instrument cluster	GO to PINPOINT TEST Q .
The generator(s) is noisy	Loose bolts/brackets Drive belt Upper generator Lower generator	GO to PINPOINT TEST R .
Radio interference	Upper generator Lower generator Wiring/routing In-vehicle entertainment system	GO to PINPOINT TEST S .
Dual generator upper fault detected (P0620)	Upper generator connector C102a unplugged B+ circuit fusible links B+ circuit 36 A circuit 35 I circuit 1183 Upper generator	GO to PINPOINT TEST T .
Dual generator lower fault detected (PI 148)	Lower generator connector C125la unplugged B+ circuit fusible links B+ circuit 36 A circuit 35 I circuit 1185 Lower generator	GO to PINPOINT TEST U .
Dual generator lower circuit fault detected (PI 149)	I circuit 1185 Lower generator	GO to PINPOINT TEST V .
Dual generator battery lamp circuit fault detected (P0623)	Lamp circuit 904 Instrument cluster	REFER to INSTRUMENT CLUSTER .