2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2428
Control Module References (See: Testing and Inspection/Programming and Relearning)for scan tool information
Circuit/System Testing
1. Verify that DTC P0231, P0232 or P023F are not set.
瀚慖f any of those codes are set, refer to DTC P0231, P0232, or P023F (See: P Code Charts/P0231).
2. Ensure that the entire undercarriage of the vehicle is clean, especially around the area where the K27 fuel pump control module is located.
Clear all codes from the K27 fuel pump control module and test drive the vehicle. Verify that DTC P1255 or P064A do not set.
瀚慖f DTC P1255 or P064A reset, replace the K27 fuel pump control module.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning)for fuel pump control module replacement, setup, and
programming
P1258
DTC P1258
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 Descriptor
DTC P1258
- Engine Coolant Over temperature - Protection Mode Active
Circuit/System Description
The engine control module (ECM) uses the engine coolant temperature (ECT) sensor to monitor the engine for an over-termperature condition. This
condition occurs when the coolant temperature is above a calibrated value for a calibrated length of time. The ECM will disable half of the
cylinders by turning OFF the fuel injectors. By disabling half of cylinders, the ECM is able to reduce the temperature of the coolant.
Conditions for Running the DTC
The engine is operating.
Conditions for Setting the DTC
All V8
The coolant temperature is warmer than 129掳C (264掳F) for greater than 10 seconds.
6.0L-Hybrid
The coolant temperature is warmer than 132掳C (270掳F) for greater than 10 seconds.
Action Taken When the DTC Sets
* DTC P1258 is a Type A DTC.
* The engine will operate in the Overheated Engine Protection Operating Mode.
* The engine coolant temperature indicator lamp, if equipped, will illuminate.
* The driver information center (DIC), if equipped, may display a message.
* If the protection mode is active and an ECT sensor DTC sets, the protection mode will activate during the next drive cycle until the ECT
sensor DTC runs and passes.
Conditions for Clearing the DTC
