P1248 Possible Causes
- Damaged MAP hose
- Low turbo boost
- Intake manifold or crossover tube leaks
- Faulty MAP sensor
- Faulty Powertrain Control Module (PCM)
How is P1248 Code Repair Performed?
Start by checking the “Possible Causes” listed above. Visually inspect the wiring harness and associated connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
- Engine light on (or maintenance engine warning light soon)
P1248 Meaning
The boost pressure sensor responds to changes in pressure in the intake manifold. This pressure is created by the turbocharger and changes with the accelerator pedal position (APP) and engine speed. The Powertrain Control Module (PCM) uses this information to assist in diagnosing the barometric pressure sensor (BARO) and to provide engine overboost protection. The boost pressure sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit. The PCM supplies 5 volts to the boost pressure sensor on the 5-volt reference circuit 2 and provides ground on a low reference circuit. The boost pressure sensor provides a signal to the PCM on a signal circuit relative to pressure changes. The PCM monitors the boost pressure sensor signal for voltage outside the normal range. The PCM calculates a predicted value for the boost pressure sensor. The PCM then compares the predicted value to the actual signal.