2010 Cadillac CTS Sedan AWD V6-3.6L Page 1224
Circuit/System Description
The engine control module (ECM) monitors the control circuit of the brake booster pump relay. The ECM supplies ground through the pump relay
control circuit which then supplies B+ voltage to actuate the brake booster pump. B+ voltage is supplied at all times to the coil side of the pump
relay.
Conditions for Running the DTC
P258A, P258C, P258D
Ignition ON.
P258B
* Engine Running
* Vacuum pump is activated for greater than 1.6 seconds.
Conditions for Setting the DTC
P258A, P258C
The ECM detects an open/high resistance on the relay coil control circuit.
P258B
The ECM detects an excessive difference in vacuum levels between the power brake booster and the manifold absolute pressure (MAP).
P258D
The ECM detects a short to voltage on the relay control circuit.
Action Taken When the DTC Sets
DTC P258A, P258B, P258C, P258D are Type B DTCs.
Conditions for Clearing the DTC
DTC P258A, P258B, P258C, P258D are Type B DTCs.
Reference Information
Schematic Reference
Hydraulic Brake Schematics (See: Brakes and Traction Control/Hydraulic System/Diagrams/Electrical Diagrams)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Brake Booster Vacuum Assist Description and Operation (See: Brakes and Traction Control/Hydraulic System/Description and Operation/Brake
Booster Vacuum Assist Description and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
