D: Manifold Absolute Pressure (MAP) Sensor
Introduction
Introduction
1997 PCED OBDII-Diesel | SECTION 5C: Pinpoint Tests |
D: Manifold Absolute Pressure (MAP) Sensor Introduction | D: Pinpoint Tests |
The manifold absolute pressure (MAP) sensor is a variable capacitance sensor that, when supplied with a 5-volt reference signal from the powertrain control module (PCM), produces a digital frequency signal that indicates pressure.
Smoke Control — The MAP signal is used to control smoke by limiting fuel quantity during acceleration until a specified boost pressure is obtained.
Dynamic Injection Timing — Optimizes injection timing for boost pressure measured.
A MAP signal that is detected by the PCM to be out of range or at an incorrect value for specific conditions will cause the PCM to ignore the MAP signal and operate the engine from an inferred boost pressure signal.
After removing connectors, always check for damaged pins, corrosion, loose terminals, etc.
P0236 = Turbo Boost Sensor A Circuit Performance
P0237 = Turbo Boost Sensor A Circuit Low Input
P0238 = Turbo Boost Sensor A Circuit High Input
P1247 = Turbo Boost Pressure Low
P1248 = Turbo Boost Pressure Not Detected
| Hz | PSIA | KPA |
|---|---|---|
| 94 | 10 | 70 |
| 102 | 12 | 83 |
| 109 | 14 | 97 |
| 111 | 14.7 | 101 |
| 116 | 16 | 110 |
| 123 | 18 | 124 |
| 130 | 20 | 138 |
| 138 | 22 | 152 |
| 145 | 24 | 166 |
| 152 | 26 | 179 |
| 159 | 28 | 193 |
| 167 | 30 | 207 |
| 174 | 32 | 221 |
| 181 | 34 | 234 |
| 188 | 36 | 248 |
| 195 | 38 | 262 |
| 203 | 40 | 276 |
| 210 | 42 | 290 |
| 217 | 44 | 303 |
| D: Pinpoint Tests |