ShopBaseComplete shop management for auto repair shops · $249/mo
Try ShopBase →
Home › Waveforms › 2019 Jeep Wrangler › Manifold Absolute Pressure Sensor

Manifold Absolute Pressure Sensor

2019 Jeep Wrangler · 3.6L V6

1.5V1.1V0.8V500ms/div | 1V/divdc-variable
Sensor Type
piezoresistive
Waveform Type
dc-variable
Location
Mounted on intake manifold plenum, passenger side rear of engine, integrated sensor with vacuum reference to manifold
Pins
3-pin connector
0
Timebase
500ms/div
Voltage Scale
1V/div
Trigger
N/A - DC signal

Wiring

Black/Light Blue (ground), Violet/White (5V reference from PCM), Dark Green/Orange (MAP signal to PCM)

Expected Voltage Range

At Idle
0.8V to 1.5V
At Higher RPM
4V to 4.7V

Expected Pattern

Smooth analog DC voltage inversely proportional to vacuum, 0.8-1.5V at idle (16-20 inHg vacuum), rising to 4.0-4.7V at WOT (atmospheric pressure)

Known-Good Waveform

At idle in Park/Neutral, MAP sensor should read 0.8-1.5V corresponding to 16-20 inHg of manifold vacuum at sea level. Key-on-engine-off (KOEO) voltage should read 4.3-4.7V representing atmospheric pressure. During snap throttle opening, voltage should rise smoothly and quickly to near KOEO values, then drop back to idle vacuum levels. The 3.6L Pentastar with VVT will show slight MAP fluctuations during cam phaser operation.

Common Failure Patterns

Idle voltage reads high (2.0-3.0V) indicating low vacuum, rough idle, poor fuel economy, may set lean codes
Cause: Vacuum leak in intake manifold, throttle body gasket, brake booster, or PCV system - common at intake manifold bolts on 3.6L which can loosen
Related DTCs: P0171, P0174, P0106, P0107
MAP voltage stuck at or near KOEO voltage (4.5V) regardless of engine vacuum conditions
Cause: Failed MAP sensor diaphragm, blocked vacuum port, or internal sensor failure
Related DTCs: P0106, P0107, P0108
Rapid fluctuations or noise on MAP signal, erratic voltage readings not corresponding to throttle position
Cause: Corroded connector, damaged signal wire causing EMI interference, or failing sensor element
Related DTCs: P0106, P0107, P0108
KOEO voltage reads significantly different from barometric pressure or voltage slowly drifts over time
Cause: Sensor reference voltage issue (should be 5.0V ±0.1V), MAP sensor internal calibration drift, or contamination in sensor port
Related DTCs: P0106, P2227, P2228

Diagnostic Tips

The 3.6L Pentastar uses MAP sensor for load calculation and backup to MAF in speed-density mode. Always verify 5V reference voltage at sensor connector is stable. Common vacuum leak points include intake manifold runner control valve, throttle body gasket, and PCV valve grommet. Compare MAP readings to known good barometric pressure for your altitude before condemning sensor.

Related Diagnostic Trouble Codes

P0105P0106P0107P0108P0109
Always confirm waveform data with your vehicle's OEM service manual before diagnosing.

Free, no signup. View all waveforms for this vehicle