For a complete wiring diagram Refer to Section 8W.When Monitored:Ignition on. In plant mode only.Set Condition:PCM recognizes the Brake Pedal could not electrically indicate the applied (On) position with both switch inputs. One trip fault.Possible Causes(B15) BRAKE SIGNAL 1 CIRCUIT OPEN(B16) BRAKE SIGNAL 2 CIRCUIT OPENSTOP LAMP SWITCH PCMAlways perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).1. ACTIVE DTCMake sure the Stop Lamp Switch is adjusted properly before continuing.Ignition on, engine not running.With a scan tool, select View DTCs.Is the DTC Active at this time?YesGo To 2NoRefer to the INTERMITTENT CONDITION Diagnostic Procedure.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)2. STOP LAMP SWITCH OPERATIONTurn the ignition off.Disconnect the Stop Lamp Switch harness connector.Measure the resistance between the (Z914) Ground circuit terminal and the (B15) Brake Signal 1 circuit terminal in the Stop Lamp Switch.Apply and release the Stop Lamp Switch while monitoring the ohmmeter.Does the resistance change from below 5.0 ohms to open circuit when pressing and releasing the brake pedal switch?YesGo To 3NoReplace the Stop Lamp Switch.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)3. STOP LAMP SWITCH OPERATIONMeasure the resistance between the (F941) Fused Ignition Switch terminal and the (B16) Brake Signal 2 circuit terminal in the Stop Lamp Switch.Apply and release the Stop Lamp Switch while monitoring the ohmmeter.Does the resistance change from below 5.0 ohms to open circuit when pressing and releasing the Stop Lamp switch?YesGo To 4NoReplace the Stop Lamp Switch.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)4. (B15) BRAKE SIGNAL 1 CIRCUIT OPEN

Disconnect the C3 PCM harness connector.Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.Measure the resistance of the (B15) Brake Signal 1 circuit from the Stop Lamp Switch harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 5NoRepair the open in the (B15) Brake Signal 1 circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)5. (B16) BRAKE SIGNAL 2 CIRCUIT OPEN

Measure the resistance of the (B16) Brake Signal 2 circuit from the Stop Lamp Switch harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 6NoRepair the open in the (B16) Brake Signal 2 circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)6. PCMBefore continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.Were there any problems found?YesRepair as necessary.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoReplace and program the Powertrain Control Module per Service Information.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)