Test Notes

MAP Sensor And Related Components:

SIGNAL FUNCTIONS
The Manifold Absolute Pressure (MAP) sensor is a variable capacitance sensor which, 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.

Test Schematic:

FAULT DETECTION/MANAGEMENT
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.






Connector Checks To Ground (B-)
Check with sensor connector disconnected and ignition key and all accessories OFF.





Connector Voltage Checks
Check with sensor disconnected and ignition key ON.





Harness Resistance Checks
Check with Breakout Box installed on engine harness only.





Operational Signal Checks
Check with Breakout Box installed in line with the PCM.


NOTE: After removing connectors always check for damaged pins, corrosion, loose terminals, etc..

MAP Sensor Pressure/Frequency Chart:

DTC DESCRIPTION
0236 = Turbo Boost Sensor A Circuit Performance
0237 = Turbo Boost Sensor A Circuit Low Input
0238 = Turbo Boost Sensor A Circuit High Input