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Diagnostic Trouble Code Definitions

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DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC (1) Description
B1327  Battery/Source Voltage Low
P0562  Low System Voltage
P0563  High System Voltage
P0621  High Or Low Generator Turn On Signal
P0622  (2) Out Of Range Duty Cycle Signal
P1637  (2) High Or Low Generator Turn On Signal
P1638  (2) Out Of Range Duty Cycle Signal

(1) Codes listed in this table are only for testing covered in this article. For complete DTC listing, see appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
(2) On 4.3L Engines Only.