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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2007 🢒 G5 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 DTC B3794

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    •  Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B3794 08: Cruise Control Function Request Circuit Signal Invalid

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Cruise Control Switch Supply Voltage

1

B3794 08

1

B3794 08

Cruise Control Switch Signal

B3794 08

B3794 08

1

B3794 08

1. Cruise Control Inoperative/Malfunctioning

Circuit/System Description

The cruise control switch is an input to the body control module (BCM). The BCM monitors the cruise control set/coast and resume/accelerate 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 set/coast and resume/accelerate switch signal circuit when a switch is applied.

Conditions for Running the DTC
    • The cruise switch is ON.
    • The ignition is ON.

Conditions for Setting the DTC
    • The BCM detects an invalid voltage signal on the cruise control switch signal circuit.
    • The above condition is present for greater than 1 second.

Action Taken When the DTC Sets
    • The BCM stores the DTC information into memory when the diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The Cruise Control System is disabled.

Conditions for Clearing the DTC
    • The DTC becomes history when the fault is no longer present.
    • A History DTC clears after 100 malfunction-free ignition cycles.
    • The BCM receives a clear code command from the scan tool.

Diagnostic Aids
    • Rotate the steering wheel to both steering stops and activate each cruise control switch separately. With a scan tool, observe the Cruise Control Switch parameter in the BCM Cruise Control data list. This will help eliminate the possibility of a internally open or shorted inflatable restraint steering wheel module coil.
    • For an intermittent, refer to Testing for Intermittent Conditions and Poor Connections .

Reference Information

Schematic Reference

Cruise Control Schematics

Connector End View Reference

    •  Cruise Control Connector End Views
    •  Data Communication Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Circuit/System Verification
  1. Ignition ON, observe the scan tool Cruise Control Switch parameter in the BCM while pressing the various cruise control switches. The reading should be Error.
    2. ⇒If the Cruise Control Switch parameter toggles between On, Off, Resume, and Set accordingly with the depressed switches, go to Testing for Intermittent Conditions and Poor Connections .
  2. Go to Circuit/System Testing.

Circuit/System Testing

Caution: Refer to SIR Caution in the Preface section.

Disable the inflatable restraint steering wheel module when performing this diagnostic. Refer to SIR Disabling and Enabling .

  1. Ignition OFF, remove the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .
  2. Disconnect the harness connector at the cruise control on/off switch.
  3. Ignition ON, measure for 10 volts or greater at the cruise control supply voltage circuit.
    4. ⇒If less than the specified value, check for an open/high resistance or a short to ground on the cruise control supply voltage circuit.
  4. Ignition OFF, connect the harness connector at the cruise control on/off switch. Disconnect the harness connector at the cruise control set/cruise, resume/accelerate switch.
  5. Ignition ON, cruise on/off switch ON, measure for 10 volts or greater at the cruise control switch signal circuit.
    6. ⇒If less than the specified value, check for an open/high resistance or a short to ground on the cruise control switch signal circuit between the cruise on/off switch terminal 6 and the cruise control set/cruise, resume accelerate switch terminal 6 (UK3)/terminal 3 (non UK3). If the circuit tests normal, replace the cruise on/off switch assembly.
  6. Ignition OFF, test for an open/high resistance, a short to ground, or a short to voltage in the cruise control switch signal circuit.
  7. Test the component. If the circuits and the component tests are normal, replace the BCM.

Component Testing

Caution: Refer to SIR Caution in the Preface section.

Disable the inflatable restraint steering wheel module when performing this diagnostic. Refer to SIR Disabling and Enabling .

  1. Ignition OFF, remove the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .
  2. Ignition OFF, disconnect the harness connector at the cruise control set/coast, resume/accelerate switch assembly.
  3. Measure the resistance between terminals 6 (UK3)/3 (non UK3) and 7 (UK3)/4 (non UK3) at the cruise control switch side of the connector. Individually activate and hold each cruise control function switch and compare the resistance reading to the values for the - SET and the + RES switches.
    4. ⇒If any of the resistance measurements for the - SET, and the + RES switches are not within the listed resistance values, replace the cruise control set/coast, resume/accelerate switch assembly.

Function Switch

Minimum Resistance Value

Maximum Resistance Value

- SET

1.2k Ohms

1.3k Ohms

+ RES

2.7k Ohms

3.0k Ohms

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Steering Wheel Control Switch Assembly Replacement
    •  Control Module References for BCM replacement, setup, and programming