Archives: DTC Codes

What Does Code P1126 Mean? DTC P1126 signifies a malfunction within the Throttle Position Sensor (TPS) Narrow Range Circuit. This code indicates that the Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected an anomaly in the electrical signal from the TPS, specifically when the throttle plate is operating within a critical, small […]

What Does Code P1127 Mean? DTC P1127 indicates that the Engine Control Module (ECM), also known as the Powertrain Control Module (PCM), has detected that the downstream oxygen sensor (often referred to as the post-catalytic converter O2 sensor, or Sensor 2 for a specific bank) has not reached its optimal operating temperature within a specified […]

What Does Code P1128 Mean? Diagnostic Trouble Code (DTC) P1128 signifies that the Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected an inconsistency in the signals received from the upstream (pre-catalytic converter) heated oxygen sensors. Specifically, P1128 indicates that the electrical connectors for the Bank 1 Sensor 1 (B1S1) and Bank 2 […]

What Does Code P1129 Mean? DTC P1129, or “Downstream Heated O2 Sensors Swapped,” indicates that the Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected an illogical or swapped electrical connection between the post-catalytic converter (downstream) heated oxygen sensors on multi-bank engines (typically V6, V8, or V10 configurations). Specifically, the ECM observes the […]

What Does Code P1130 Mean? DTC P1130 signifies “Lack Of HO2S Switch – Adaptive Fuel At Limit,” specifically referring to the upstream Heated Oxygen Sensor (HO2S) for Bank 1, Sensor 1. This code is triggered when the Powertrain Control Module (PCM) detects that the Bank 1, Sensor 1 HO2S is not oscillating sufficiently or at […]

What Does Code P1131 Mean? DTC P1131 signifies that the Engine Control Module (ECM), often referred to as the Powertrain Control Module (PCM), has detected an anomaly in the performance of the Bank 1, Sensor 1 Heated Oxygen Sensor (HO2S). Specifically, it indicates a “Lack Of HO2S Switch – Sensor Indicates Lean.” In a healthy […]

What Does Code P1132 Mean? DTC P1132 signifies that the Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected a “Lack Of HO2S Switch – Sensor Indicates Rich” condition specifically for the upstream heated oxygen sensor (HO2S) in Bank 1 Sensor 1 (B1S1). The primary function of B1S1 is to monitor the oxygen […]

What Does Code P1133 Mean? The P1133 diagnostic trouble code indicates that the Engine Control Module (ECM), often referred to as the Powertrain Control Module (PCM), has detected an anomaly in the operational switching frequency or amplitude of the Heated Oxygen Sensor (HO2S) designated as Bank 1 Sensor 1. This sensor is critically positioned in […]

What Does Code P1134 Mean? DTC P1134 signifies an issue with the Heated Oxygen Sensor (HO2S) transition time ratio for Bank 1 Sensor 1. This code specifically indicates that the Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected that the upstream oxygen sensor (pre-catalytic converter, cylinder bank containing cylinder #1) is not […]

What Does Code P1135 Mean? DTC P1135 signifies an intermittent fault detected within the Accelerator Pedal Position Sensor (APPS) ‘A’ circuit. The Engine Control Module (ECM), or Powertrain Control Module (PCM), monitors multiple dedicated voltage signals from the APPS to precisely interpret the driver’s throttle demand in drive-by-wire systems. The APPS typically incorporates two or […]