Possible causes
– Faulty Accelerator Pedal Position Sensor
– Accelerator Pedal Position Sensor harness is open or shorted
– Accelerator Pedal Position Sensor circuit poor electrical connection
– Accelerator Pedal Position Sensor harness is open or shorted
– Accelerator Pedal Position Sensor circuit poor electrical connection
When is the code detected?
The Powertrain Control Module (PCM) detects that the difference between Accelerator Pedal Position (APP) sensor 1 and APP sensor 2 is more than the predicted value.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P1125 GMC Description
The accelerator pedal position (APP) sensor 1 and the APP sensor 2 are potentiometer type sensors, each with the following circuits:
? A 5-volt reference circuit
? A low reference circuit
? A signal circuit
The control module provides the APP sensors with a 5-volt reference circuit and a low reference circuit. The APP sensors then provide the control module signal voltages proportional to pedal movement. The APP sensor 1 signal voltage is low at rest and increases as the pedal is depressed.
The APP sensor 2 signal voltage is low at rest and increases as the pedal is depressed. When the control module detects that the APP sensor 1 and the APP sensor 2 signal circuits are out of correlation with each other, DTC P1125 sets.
? A 5-volt reference circuit
? A low reference circuit
? A signal circuit
The control module provides the APP sensors with a 5-volt reference circuit and a low reference circuit. The APP sensors then provide the control module signal voltages proportional to pedal movement. The APP sensor 1 signal voltage is low at rest and increases as the pedal is depressed.
The APP sensor 2 signal voltage is low at rest and increases as the pedal is depressed. When the control module detects that the APP sensor 1 and the APP sensor 2 signal circuits are out of correlation with each other, DTC P1125 sets.
GMC Technical Service Bulletins for P1125 code
2003 GMC SIERRA ENGINE AND ENGINE COOLING:ENGINE
2003 GMC TOPKICK ENGINE AND ENGINE COOLING:ENGINE
2003 GMC W SERIES ENGINE AND ENGINE COOLING:ENGINE
2003 GMC YUKON ENGINE AND ENGINE COOLING:ENGINE
2003 GMC YUKON DENALI ENGINE AND ENGINE COOLING:ENGINE
2003 GMC ENVOY ENGINE AND ENGINE COOLING:ENGINE
1999 GMC B7 VEHICLE SPEED CONTROL:LINKAGES
1999 GMC G2 VAN VEHICLE SPEED CONTROL:LINKAGES
1999 GMC G3 VAN VEHICLE SPEED CONTROL:LINKAGES
2004 GMC SAVANA ENGINE AND ENGINE COOLING