P CODE FAMILY

Powertrain code references — Page 54.

Engine, transmission and powertrain diagnostic references. Exact vehicle and module context still matters.

Buick / Cadillac +5

P1537

These are code references, not a list of confirmed faults on every vehicle. Read the source and applicability notes, then match the exact vehicle, year, engine and scan report.

A/C Request Circuit Low Voltage

Intake Manifold Runner Control Stuck Open

Engine Shutoff Solenoid Malfunction

A/C Request Circuit High Voltage

Intake Manifold Runner Control Stuck Open

Engine Shutoff Solenoid Open Short To Ground

Air Conditioning (A/C) Clutch Feedback Circuit High Voltage

Power to A/C Compressor Clutch Circuit Exceeded Normal Current Draw

Clutch Pedal Switch Signal Fault

Pedal Position Sensor

A/C System High Pressure

Vehicle Speed Sensor Malfunction

Vehicle Speed Sensor High Input

Pedal Position Sensor Double Error

A/C High Side Over Temperature

Fuel Pump Relay Circuit Open

Pedal Position Sensor Electrical

A/C System High Pressure High Temperature

Throttle Actuation Potentiometer Range Performance

Pedal Position Sensor

A/C System Performance

Throttle Actuation Potentiometer Signal Too Low

Pedal Position Sensor

A/C Refrigerant Condition Very Low

High Exhaust Temperature Detected

Throttle Actuation Potentiometer Signal Too High

Pedal Position Sensor

A/C Clutch Relay Control Circuit

Throttle Position Control Malfunction

Pedal Position Sensor

Air Conditioning (A/C) Clutch Feedback Circuit Low Voltage

Boost Pressure Control Valve Short To B+

A/C System Performance Degraded

Boost Pressure Control Valve Short To Ground

A/C Recirculation Circuit

Boost Pressure Control Valve Open

Intake Manifold Temperature Valve Vacuum Actuator Connection

Boost Pressure Control Valve Open Short To Ground

Idle Speed Control Valve Closing Solenoid Control Circuit Electrical

Power Steering Pressure Sensor Out of Self-Test Range

TCC Solenoid Valve

Charge Pressure Deviation

A Camshaft Position Actuator Control Open Circuit Bank 1

Barometric Pressure Sensor Circuit Short To B+

A Camshaft Position Actuator Control Open Circuit Bank 1

Idle Air Control Valve Opening Coil Low Voltage

Barometric Pressure Sensor Circuit Open Short To Ground

Idle Air Control Valve Opening Coil High Voltage

Barometric Manifold Pressure Signal Ratio Out Of Range

Cruise Engaged Circuit High Voltage

Idle Speed Control Throttle Position Missing Adaptation Conditions

Electronic Variable Orifice Output

Charge Pressure Upper Limit Exceeded

A Camshaft Position Actuator Control Open Circuit Bank 1

Charge Pressure Negative Deviation

Charge Pressure Positive Deviation

Cruise Control Servo Indicates Low

Throttle Actuator Electrical Malfunction

Cruise Control Power Mangement Mode

Cruise Control Power Management Mode

Idle Speed Control Throttle Position Adaptation Malfunction

B Camshaft Position Actuator Control Open Circuit Bank 1

Cruise Control System Transaxle Not In Drive

Back-Up Voltage Circuit Malfunction

Maximum Engine Speed Exceeded

Cruise Vent Solenoid

Quantity Adjuster Deviation

Cruise Vacuum Solenoid

Powertrain Control Module +B Voltage Low

Quantity Adjuster Upper Limit Attained

Cruise Vehicle Speed Set Speed Difference Too High

Quantity Adjuster Lower Limit Attained

Control Module Selection

Cruise Control System Vehicle Accel Too High

Idle Speed Control Throttle Position Low Voltage During Adaptation

B Camshaft Position Actuator Control Open Circuit Bank 1

Cruise Servo Position Sensor

Speed Control Command Switch Out of Range High

Cruise Control Main Switch Circuit Malfunction

Cruise Control Main Switch Circuit