2010 Cadillac CTS Sedan AWD V6-3.6L Page 1854
Conditions for Running the DTCs
* The ignition is ON or the engine is operating.
* The ignition voltage is greater than 7 V.
* The DTCs run continuously once the above conditions are met.
Conditions for Setting the DTC
P2122
The APP sensor 1 voltage is less than 0.74 V for greater than 1 s.
P2123
The APP sensor 1 voltage is greater than 4.82 V for greater than 1 s.
P2127
The APP sensor 2 voltage is less than 0.63 V for greater than 1 s.
P2128
The APP sensor 2 voltage is greater than 4.82 V for greater than 1 s.
P2138
* The ECM detects that the voltage difference between APP sensor 1 and the calculated idle range is greater than 0.25 V, with a released pedal.
* The ECM detects that the voltage difference between APP sensor 2 and the calculated idle range is greater than 0.31 V, with a released pedal.
* The ECM detects that the voltage difference between APP sensor 1 and 2 is greater than 0.31 V with a partially pressed pedal.
* The ECM detects that the voltage difference between APP sensor 1 and 2 is greater than 1.70 V with a fully pressed pedal.
* The ECM detects that the voltage difference between APP sensor 1 and 2 is greater than 0.04 V when APP sensor 1 is greater than 1.17 V.
* Any of the above conditions exist for greater than 1 second, or a cumulative of 10 s.
Action Taken When the DTC Sets
DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.
Conditions for Clearing the DTC
DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.
Diagnostic Aids
Test the current output of the 5 V reference circuits if you suspect high resistance in the circuit. The current output should be greater than 80 mA
for APP 1 and greater than 50 mA for APP 2.
Reference Information
Schematic Reference
Engine Controls Schematics (LLT) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls Schematics
(LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and
Operation/Throttle Actuator Control (TAC) System Description)
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)
