DTC P1296: No 5 Volts To Map Sensor: Testing
NOTE:
If DTC P0107 is also present with DTC P1296, repair DTC P0107 before continuing with this test. See DTC P0107: MAP SENSOR VOLTAGE TOO LOW .
- Turn ignition on, engine off. Using scan tool in SENSORS MODE, read MAP sensor voltage. If MAP sensor voltage is less than 2.35 volts, go to next step. If MAP sensor voltage is 2.35 volts or more, go to step 6.
- Turn ignition off. Disconnect MAP sensor connector. Inspect connectors for damaged pins, corrosion and loose terminals. Repair connectors as necessary. On 4.7L, MAP sensor is located on front of intake manifold. On 5.9L, MAP sensor is located on front of throttle body. See Figure or Figure . Turn ignition on, engine off. Using scan tool in SENSORS MODE, read MAP sensor voltage. If MAP sensor voltage is more than 4.5 volts, replace MAP sensor. If voltage is 4.5 volts or less, go to next step.
- Turn ignition off. Ensure MAP sensor connector is still disconnected. Disconnect PCM connectors. PCM is located in engine compartment on passenger-side inner fender panel. Inspect connectors for damaged pins, corrosion and loose terminals. Repair connectors as necessary. If connectors are okay, measure resistance of MAP sensor 5-volt supply circuit (Orange wire) between PCM harness connector C1 terminal No. 17 and MAP sensor harness connector terminal No. 1 (4.7L) or No. 3 (5.9L). See Figure, Fig 1 or Fig 2 . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Orange wire between MAP sensor and PCM.
- Ensure ignition is off and MAP sensor and PCM connectors are still disconnected. Using DVOM, measure resistance of MAP sensor 5-volt supply circuit (Orange wire) between ground and MAP sensor harness connector terminal No. 1 (4.7L) or No. 3 (5.9L). If resistance is less 5 ohms, repair short to ground in Orange wire between MAP sensor and PCM. If resistance is 5 ohms or more, go to next step.
- At this time, PCM is assumed to be defective. Replace PCM.
- Start engine and allow engine to idle. Using scan tool in SENSORS MODE, read MAP sensor voltage while wiggling wiring harness and connectors between MAP sensor and PCM. If MAP sensor voltage does not change while wiggling wiring harness and connectors, test is complete. If MAP sensor voltage changes while wiggling wiring harness and connectors, repair wiring or connectors as necessary that caused MAP sensor voltage to change.