General Information

Engine Control
P2503 AMP No Battery Charge - General Information

Component Location





General Description

Battery sensor is mounted on the battery (-) terminal. It transmits battery voltage, current, temperature information to ECM. ECM controls the generating output by changing the duty cycle to the generator based on these signals.

DTC Description

ECM sets this code when the battery charging current from battery sensor is too low.

DTC Detecting Condition





Diagnostic Circuit Diagram





Signal Waveform & Data
















Fig.1) Normal waveforms of COM, FR terminal of alternator at idle.
Fig.2) Normal waveforms of COM, FR terminal of alternator under high electronic load condition
Fig.3) Normal waveforms of COM, FR terminal of alternator at ig on under connector disconnected condition.
Fig.4) Normal waveforms of COM, FR terminal of alternator at idle under connector disconnected condition.