P162C
DTC P155A or P162C
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P155A 00
- Cruise Control Switch State Undetermined
DTC P162C 00
- Vehicle Speed Limiting/Warning Switch Circuit Malfunction
Diagnostic Fault Information
Circuit/System Description
The cruise control switch is an input to the body control module (BCM). The BCM monitors the cruise control on/off, set/coast, resume/accelerate and cancel switches via the cruise control switch signal circuit in order to detect when the driver has requested to perform a cruise control function. The BCM detects a specific voltage signal on the cruise control switch signal circuit when a switch is applied. The engine control module (ECM) receives the requested cruise control switch function from the BCM via a serial data message.
Conditions for Running the DTC
* The ignition is ON.
* The cruise switch is ON.
Conditions for Setting the DTC
The BCM detects an invalid signal on the cruise control switch signal circuit and sends a serial data message to the ECM. The ECM sets these DTCs when the message is received.
Action Taken When the DTC Sets
DTC P155A 00 and P162C 00 are Type C DTCs
Conditions for Clearing the DTC
DTC P155A 00 and P162C 00 are Type C DTCs
Reference Information
Schematic Reference
Cruise Control Schematics Electrical Diagrams
Connector End View Reference
Component Connector End Views Outside Rearview Mirror - Driver
Description and Operation
Cruise Control Description and Operation Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
Engine ON, while rotating the steering wheel to both steering stops, observe the scan tool Cruise Control Switch parameter while pressing each of the cruise control switches. The parameter should toggle between On, Off, Resume, Set, and Cancel as the applicable switch is pressed.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the S70L steering wheel controls switch - left.
2. Ignition ON, test for B+ between the voltage reference circuit terminal 1 and ground.
• If less than the specified value, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 body control module.
3. Test for B+ between the voltage reference circuit terminal 1 and the signal circuit.
• If less than the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 body control module.
4. Ignition OFF, disconnect the X3 harness connector at the K9 body control module.
5. Test for infinite resistance between the signal circuit terminal 9 and ground.
• If less than the specified value, test the signal circuit for a short to ground.
6. If all circuits test normal, test or replace the S70L steering wheel controls switch - left.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Cruise Control Switch Replacement Service and Repair
* Control Module References Control Module References for BCM replacement, programming and setup