DTC P1574 ECM w/L61
Diagnostic Instructions
DTC Descriptor
DTC P1574 : Stop Lamp Switch Circuit
Diagnostic Fault Information
Circuit
| Short to Ground
| Open or High Resistance
| Short to Voltage
| Signal Performance
|
Stop Lamp Switch Signal
| P1574
| P1574
| P1574
| --
|
Circuit/System Description
The stoplamp switch is used to sense the action of the driver application of the brake pedal. The stoplamp switch will apply battery voltage to the park/stoplamp signal voltage supply circuit to illuminate the stop lamps and the center high mounted stop
lamp (CHMSL). The stoplamp switch also sends a signal to the engine control module (ECM) as well to indicate the application of the brake pedal.
Conditions for Running the DTC
| • | Battery voltage is greater than 11.5 volts. |
Conditions for Setting the DTC
The ECM detects a short to ground, short to voltage, or open on the stop lamp switch signal circuit when the brakes are applied.
Action Taken When the DTC Sets
| • | The ECM stores the DTC to memory. |
| • | The ECM will record the operating conditions at the time the diagnostic failed. The ECM stores this information in Failure Records. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists. |
| • | You issue a scan tool CLEAR DTCs command. |
| • | A history DTC will clear once 40 malfunction-free ignition cycles have occurred. |
Reference Information
Schematic Reference
Exterior Lights Schematics
Connector End View Reference
Lighting Systems Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
- Perform the stoplamp switch adjustment, refer to
Stop Lamp Switch Adjustment
, clear all DTCs, and operate the vehicle within the Conditions for Running the DTC.
| ⇒ | If DTC P1574 resets as current, test the stop lamp switch signal circuit for a short to ground, short to voltage, or open. |
- If circuits test OK, replace the ECM.
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
DTC P1574 PCM w/L66
Diagnostic Instructions
DTC Descriptor
DTC P1574 : Stop Lamp Switch Circuit
Diagnostic Fault Information
Circuit
| Short to Ground
| Open or High Resistance
| Short to Voltage
| Signal Performance
|
Stop Lamp Switch Signal
| P1574
| P1574
| P1574
| --
|
Circuit/System Description
The stoplamp switch is used to sense the action of the driver application of the brake pedal. The stoplamp switch will apply battery voltage to the park/stoplamp signal voltage supply circuit to illuminate the stop lamps and the center high mounted stop
lamp (CHMSL). The stoplamp switch also sends a signal to the powertrain control module (PCM) as well to indicate the application of the brake pedal.
Conditions for Running the DTC
| • | Battery voltage is greater than 11.5 volts. |
Conditions for Setting the DTC
The PCM detects a short to ground, short to voltage, or open on the stop lamp switch signal circuit when the brakes are applied.
Action Taken When the DTC Sets
| • | The PCM stores the DTC to memory. |
| • | The PCM will record the operating conditions at the time the diagnostic failed. The PCM stores this information in Failure Records. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists. |
| • | You issue a scan tool CLEAR DTCs command. |
| • | A history DTC will clear once 40 malfunction-free ignition cycles have occurred. |
Reference Information
Schematic Reference
Exterior Lights Schematics
Connector End View Reference
Lighting Systems Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
- Perform the stoplamp switch adjustment, refer to
Stop Lamp Switch Adjustment
, clear all DTCs, and operate the vehicle within the Conditions for Running the DTC.
| ⇒ | If DTC P1574 resets as current, test the stop lamp switch signal circuit for a short to ground, short to voltage, or open. |
- If circuits test OK, replace the PCM.
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
DTC P1574 TCM w/L61 w/MN5
Diagnostic Instructions
DTC Descriptor
DTC P1574 : Stop Lamp Switch Circuit
Diagnostic Fault Information
Circuit
| Short to Ground
| Open or High Resistance
| Short to Voltage
| Signal Performance
|
Stop Lamp Switch Signal
| P1574
| P1574
| P1574
| --
|
Circuit/System Description
The stoplamp switch is used to sense the action of the driver application of the brake pedal. The stoplamp switch will apply battery voltage to the park/stoplamp signal voltage supply circuit to illuminate the stop lamps and the center high mounted stop
lamp (CHMSL). The stoplamp switch also sends a signal to the Transmission control module (TCM) as well to indicate the application of the brake pedal.
Conditions for Running the DTC
| • | Battery voltage is greater than 11.5 volts. |
Conditions for Setting the DTC
The TCM detects a short to ground, short to voltage, or open on the stop lamp switch signal circuit when the brakes are applied.
Action Taken When the DTC Sets
| • | The TCM stores the DTC to memory. |
| • | The TCM will record the operating conditions at the time the diagnostic failed. The TCM stores this information in Failure Records. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists. |
| • | You issue a scan tool CLEAR DTCs command. |
| • | A history DTC will clear once 40 malfunction-free ignition cycles have occurred. |
Reference Information
Schematic Reference
Exterior Lights Schematics
Connector End View Reference
Lighting Systems Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
- Perform the stoplamp switch adjustment, refer to
Stop Lamp Switch Adjustment
, clear all DTCs, and operate the vehicle within the Conditions for Running the DTC.
| ⇒ | If DTC P1574 resets as current, test the stop lamp switch signal circuit for a short to ground, short to voltage, or open. |
- If circuits test OK, replace the TCM.
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
