2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1920
2. Ignition OFF, disconnect the X1 harness connector at the G13 generator.
3. Ignition ON, test for less than 1 V between the control circuit terminal 1 and ground.
瀚慖f greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
4. Engine running, test for greater than 3 V between the control circuit terminal 1 and ground.
瀚慖f less than the specified range, test the control circuit for a short to ground, or an open/high resistance. If the circuit tests normal, replace
the K20 ECM.
5. If all circuits test normal, test or replace the G13 generator.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Generator Replacement (LF1) (See: Starting and Charging/Charging System/Alternator/Service and Repair)Generator Replacement (LAU)
(See: Starting and Charging/Charging System/Alternator/Service and Repair)
* Control Module References (See: Testing and Inspection/Programming and Relearning)for ECM replacement, setup, and programming
P2501
DTC P2500 or P2501
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions)provides an overview of each diagnostic category.
DTC Descriptors
DTC P2500
- Generator L-Terminal Circuit Low Voltage
DTC P2501
- Generator L-Terminal Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The engine control module (ECM) uses the generator turn on control circuit, or L-terminal circuit, to control the load of the generator on the engine.
A high side driver in the ECM applies a voltage to the voltage regulator. This controls the voltage regulator to turn the field circuit ON and OFF.
The ECM monitors the state of the generator turn ON control circuit. The ECM should detect low voltage on generator turn on control circuit when
the ignition is ON and the engine is OFF, or when the charging system malfunctions. With the engine running, the ECM should detect high voltage
on the generator turn on control circuit. The ECM performs tests to determine the status of the generator turn on control circuit.
Conditions for Running the DTC
P2500
The engine is running.
P2501
* The ignition is ON.
* The engine is OFF.
Conditions for Setting the DTC
