Advanced Diagnostics

DTC P16BC: Alternator FR Terminal Circuit/IGP Low Voltage




General Description
The alternator is driven by the engine and generates electricity to supply the necessary power to the electrical load and to charge the battery. The alternator voltage target values of 14.5 V and 12.5 V are achieved by switching the alternator control mode (controlled by the powertrain control module (PCM)). The alternator output signal is sent to the PCM, and it varies according to the battery battery's state of charge, the electrical load, and the engine rpm.

When the engine speed is a specified value and the IGP terminal voltage is below a set value when the alternator is in the 14.5 V mode, and the alternator power generation amount is a set range or less, and this condition continues more than a set time, the PCM detects a malfunction and a DTC is stored.




Monitor Execution, Sequence, Duration, DTC Type, OBD Status




Enable Conditions

Malfunction Threshold
The IGP terminal voltage is 12.0 V or less, and the alternator power generation amount is 0.5 % or less for at least 60 seconds.

Driving Pattern
1. Start the engine.
2. Maintain an engine speed of 500 rpm to 3,000 rpm.
3. Turn on the headlights (high beam) and rear window defogger.

Diagnosis Details

Conditions for illuminating the indicator
When a malfunction is detected, the DTC and the freeze frame data are stored in the PCM memory. The MIL does not come on.

Conditions for clearing the DTC
The DTC and the freeze frame data can be cleared by using the scan tool Clear command or by disconnecting the battery.