Powertrain Controls - ECM/PCM

DTC Code 16 System Low Voltage:

Charging System Voltage Wiring Diagram:

Circuit Description:

DTC 16 will set when the ignition is "ON" and the engine speed is greater than 1000 rpm and the ECM is sensing an ignition voltage input of less than 8 volts for more than two seconds.

Test Description: Numbers below refer to circled numbers on the diagnostic chart.

1. Test generator output to determine proper operation of the voltage regulator. Run engine above 1000 rpm and measure voltage across the battery. If less than 8 volts, repair generator.

Diagnostic Aids:

An intermittent may be caused by a poor connection, rubbed through insulation, a wire broken inside the insulation or poor ECM grounds.

Intermittent Test: If connections and harness checks OK, monitor battery voltage with the scan tool while moving related connectors. If the failure is induced, the battery voltage will abruptly change. This may help to isolate the location of the malfunction.