Test Notes

ICP Sensor And Related Components:

SIGNAL FUNCTIONS
The Injection Control Pressure (ICP) sensor is a variable capacitance sensor that, when supplied with a 5 volt reference signal from the Powertrain Control Module (PCM), produces a linear analog voltage signal that indicates pressure.

The ICP sensor's primary function is to provide a feedback signal to indicate rail pressure so that the PCM can command the correct injector timing and pulse width and the correct injection control pressure for proper fuel delivery at all speed and load conditions.

Test Schematic:

DETECTION/MANAGEMENT
If the PCM detects a malfunctioning ICP sensor the CHECK ENGINE light is illuminated and the PCM will go to open loop control of injection control pressure. (Operate from an estimated ICP pressure.)





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.

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

ICP Sensor Pressure/Voltage Chart:

DTC DESCRIPTIONS
1280 = Signal voltage was less than 0.039 volts for more than 0.10 seconds.
1281 = Signal voltage was greater than 4.90 volts for more than 0.10 seconds.
1212 = Signal voltage was greater than 1.625 volts with key ON/engine OFF.