PowertrainP0621

Serious

Severity: Serious - have it checked soon

Generator Lamp L Control Circuit

31 brands affected · Generic SAE J2012 description.

Key terms: Control module: a small computer that runs one part of the car · SAE J2012: the standard generic code list · Powertrain: engine, transmission and emissions

Safety: This code relates to the charging system. The battery may go flat and the car may stall.

1What it means in plain English

The engine computer or one of its output circuits has a fault.

2Common causes

Engine control module fault
Power or ground connection problem
Low battery or charging voltage
Wiring short or open circuit
Software or memory fault

3Can I drive?

Serious · drive with care

If the engine runs normally, drive carefully to a workshop for diagnosis. If it runs badly, stalls, or will not restart, have the car towed.

This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.

4Brand data 31

Brand	Code	Description	System
Ashok Leyland CV	P0621	Generator Lamp L Control Circuit SAE	Powertrain
BAIC Motor	P0621	Generator Lamp/L Terminal Circuit Brand	Powertrain
BMW	P0621	Generator Lamp L Control Circuit SAE	Powertrain
BYD	P0621	Generator Lamp/L Terminal Circuit Brand	Powertrain
Chery	P0621	Generator Lamp/L Terminal Circuit Brand	Powertrain
Daewoo	P0621	Generator Lamp/L Terminal Circuit Brand	Powertrain
DFFS	P0621	ECU fault Brand	Powertrain
DFFX	P0621	Generator Lamp/L Terminal Circuit Brand	Powertrain
DFXK	P0621	Generator L terminal circuit open Brand	Powertrain
EOBD	P0621	Generatorlampa/L-terminalkrets Brand	Powertrain
Ford	P0621	Generator Lamp L Control Circuit SAE	Powertrain
Geely	P0621	Generator Lamp/L Terminal Circuit Brand	Powertrain
GM	P0621	Circuit borne L générateur Brand	Powertrain
Great Wall	P0621	Engine L terminal fault Brand	Powertrain
Hafei	P0621	Generator Lamp/L Terminal Circuit Brand	Powertrain
Holden	P0621	Generator L-Terminal Circuit Brand	Powertrain
Hyundai	P0621	Generator Lamp L Control Circuit SAE	Powertrain
Isuzu	P0621	Generator Lamp L Control Circuit SAE	Powertrain
Land Rover	P0621	Generator lamp terminal circuit Brand	Powertrain
Mazda	P0621	Generator Lamp L Control Circuit SAE	Powertrain
Mitsubishi	P0621	Alternator L terminal Brand	Powertrain
Opel	P0621	Circuit borne L générateur Brand	Powertrain
Peugeot	P0621	Generator Lamp L Control Circuit SAE	Powertrain
Porsche	P0621	Ladekontrollleuchte Brand	Powertrain
Proton	P0621	Alternator L terminal Brand	Powertrain
Saab	P0621	Circuit borne L générateur Brand	Powertrain
MG (SAIC)	P0621	Generator Lamp/L Terminal Circuit Brand	Powertrain
SWM Motor	P0621	Generator L terminal failure Brand	Powertrain
Tata	P0621	Generator Lamp/L Terminal Circuit Brand	Powertrain
Toyota	P0621	ECU fault (expand system) Brand	Powertrain
Volkswagen	P0621	SAE: Generator Lamp L Terminal Circuit Brand	Powertrain

Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.

5Extended variant codes 3

These 7-character codes are manufacturer-specific variants of P0621 and may be reported by some scan tools.

Brand	Code	Description	System
SsangYong	P062100	Alternator short circuit to ground Brand	Powertrain
SsangYong	P062114	Alternator driving circuit short to ground Brand	Powertrain
SsangYong	P062115	Alternator driving circuit short to battery (+) Brand	Powertrain

6Related codes

Browse Pxxx codes or P062xx codes.