Workshop Manuals Factory service & repair Vauxhall
Vauxhall Astra J11 · Engine
11 · Engine

DTC P0625 or P0626

Make
Vauxhall
Model
Astra J
Section
Engine Electrical › Other Information › DTC P0625 or P0626
EngineDTC P0625 or P0626

DTC P0625 or P0626

Diagnostic Instructions

•  Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
•  Review Strategy Based Diagnosis for an overview of the diagnostic approach.
•  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0625: Generator F-Terminal Circuit Low Voltage
DTC P0626: Generator F-Terminal Circuit High Voltage

Diagnostic Fault Information



Circuit
Short to Ground
Open/High Resistance
Short to Voltage
Signal Performance

B+
P0622, P0625
P0622, P0625
-
-

Control
P0621, P2500
P0621, P2500
P0621, P2501
-

Signal
P0622, P0625
P0622, P0625
P0622, P0626
P0622
 

Circuit/System Description

The engine control module (ECM) uses the generator field duty cycle control circuit, or F-terminal circuit, to monitor the duty cycle of the generator. The generator field duty cycle control circuit connects to high side of the field windings in the generator. A pulse width modulated (PWM) high side driver in the voltage regulator turns the field windings ON and OFF. The ECM uses the PWM control input to determine the generator load on the engine. This allows the ECM to adjust the idle speed to compensate for high electrical loads. The ECM monitors the status of the generator field duty cycle control circuit. When the ignition is ON and the engine is OFF, the ECM should detect a duty cycle near 0%. When the engine is running, the duty cycle should be between 5-99%.

Conditions for Running the DTC

•  Ignition ON engine OFF, for the Ignition ON test.
•  Engine running, engine speed less than 3 000 RPM for the RUN test.

Conditions for Setting the DTC

•  DTC P0621 is not set.
•  Ignition ON engine OFF, the ECM detects a PWM signal that is greater than 65% for 5 s.
•  Engine running, the ECM detects a PWM signal that is less than 5% for 15 s.

Action Taken When the DTC Sets

DTC P0625 or P0626 are C type DTCs.

Conditions for Clearing the DTC

DTC P0625 or P0626 are C type DTCs.

Reference Information


Schematic Reference

Starting and Charging Schematics


Connector End View Reference

Component Connector End Views


Description and Operation

Charging System Description and Operation


Electrical Information Reference


DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions


Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Engine running, observe the scan tool Generator - F Terminal Control Circuit parameter. The Generator - F Terminal Control Circuit parameter should display between 5-95% depending on the actual turned on accessories.

Circuit/System Testing

1. Verify that a test lamp illuminates between the G13 Generator B+ output circuit terminal 1 X1 and ground.
⇒ If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
2. Ignition OFF, disconnect the X2 harness connector at the G13 Generator and the appropriate harness connector at the K20 Engine Control Module.
3. Test for less than 5 Ω between the X2 harness connector F-terminal and the appropriate harness connector at the K20 Engine Control Module as listed below:
  •  LBS or LSF - X1 terminal 77
  •  LDE or LLU - X2 terminal 21
  •  LPL - X2 terminal 80
⇒ If not the specified value, test the F-terminal circuit for an high/open resistance.
4. Test for infinite resistance between the G13 Generator harness connector F-terminal and ground.
⇒ If less than the specified range, test for short to ground or a short to voltage.
5. Connect the harness connector at the K20 Engine Control Module.
6. Adapt the G13 Generator L-terminal to the X2 harness connector L-terminal.
7. Engine run at 2 500 RPM, verify the battery voltage is 12.6-15 V.
⇒ If not the specified value, refer to Charging System Test . If the circuit tests normal, test the G13 Generator before replacing.
8. If the circuit tests normal, replace the K20 Engine Control Module.

Component Testing

Dynamic Test

1. Connect a oscilloscope at the G13 Generator terminal B+ X1 and the G13 Generator generator housing.
2. Engine run at 2 500 RPM.
3. Compare the pictured signal with the following references Generator Oscilloscope Information .

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•  Control Module References for ECM replacement, setup and programming

Parts & tools for this job For Vauxhall Astra

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