DC: Injection Control Pressure (ICP) Sensor Introduction 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. Detection/Management If the PCM detects a malfunctioning ICP sensor (sensor out of range high or low), the CHECK ENGINE light is illuminated and the PCM will go to open loop control of injection control pressure. (Operate from an estimated injection control pressure.) te After removing connector, check for damaged pins, corrosion, loose terminals, etc. DTC Descriptions P1210 = ICP excessive at key on P1212 = ICP voltage not at expected level
P1280 = ICP circuit out of range low P1281 = ICP circuit out of range high P1284 = ICP failure aborts KOER Cylinder Contribution Self Test Pressure (PSI) Pressure (MPA) Sensor Voltage 0 0 0.02 200 1.5 0.4 400 3 0.73 600 4 0.96 800 5.5 1.2 1000 7 1.4 1200 8 1.6 1400 9.7 1.9 1600 11 2.1 1800 12.4 2.3 2000 13.8 2.6 2200 15.2 2.8 2400 16.5 3 2600 18 3.3 2800 19.3 3.5 3000 20.6 3.8 DC1 CHECK FOR BIASED ICP SENSOR Warm up engine. Turn off engine for one minute. KOEO. Refer to Section 2, Diagnostic Methods, Parameter Identification (PID), Selecting Parameter Identification (PID). Select PIDs ICP and ICP V. Does ICP PID read greater than 0 kpa (0 psi) or ICP V PID read greater than 0.30 V? GO to DC2. GO to Symptom Chart 7.
DC2 DIAGNOSTIC TROUBLE CODE (DTC) P1280 DTC P1280 indicates injector control signal circuit out of range low was detected during KOEO Self Test or during continuous diagnostic monitoring. Possible causes: biased ICP sensor/pcm open ICP sensor circuit short to SIG RTN or PWR GND on ICP sensor circuit open in VREF circuit Disconnect ICP sensor harness connector. Measure voltage between VREF pin B and battery ground. Is the voltage between 4.5 and 5.5 V? GO to DC3. REPAIR open in VREF circuit 351 (BR/WH). RESTORE vehicle. CLEAR DTCs DC3 SIGNAL RETURN CIRCUIT CHECK Measure voltage between VREF pin B and signal return pin A. Key on. Was voltage between 4.5 and 5.5 V? GO to DC4. REPAIR open in signal return circuit 359 (GY/RD). RESTORE vehicle. CLEAR DTCs DC4 ICP SIGNAL CIRCUIT CHECK Install breakout box; leave PCM disconnected. Measure resistance between PCM test pin 87 and pin C at ICP sensor harness connector. GO to DC5. REPAIR open in signal circuit 812 (DB/LG). RESTORE vehicle. CLEAR DTCs and RETEST.
DC5 VREF CIRCUIT CHECK Measure resistance between PCM test pin 90 and pin B at ICP sensor harness connector. GO to DC6. REPAIR open in VREF circuit 351 (BR/WH). RESTORE vehicle. CLEAR DTCs DC6 SIGRTN CIRCUIT CHECK Measure resistance between PCM test pin 91 and pin A at ICP sensor harness connector. GO to DC7. REPAIR open in SIG RTN circuit 359 (GY/RD). RESTORE vehicle. CLEAR DTCs DC7 SENSOR SIGNAL CIRCUIT SHORT TO GROUND Measure resistance between PCM test pin 87 and PCM test pins 25, 51, 77, 91 and 103. GO to DC8. REPAIR short to ground in signal wire circuit 812 (DB/LG). RESTORE vehicle. CLEAR DTCs DC8 CHECK FOR SHORT ON PIN 87 Connect breakout box to PCM. Measure resistance between PCM test pin 87 and PCM test pins 25, 91, 51, 77 and 103. vehicle. CLEAR DTCs INSTALL a new PCM. RESTORE vehicle. CLEAR DTCs
DC9 DIAGNOSTIC TROUBLE CODE (DTC) P1281 DTC P1281 indicates injector control pressure circuit out of range high during KOEO Self Test or during continuous diagnostic monitoring. Possible causes: biased ICP sensor/pcm ICP circuit shorted to VREF Disconnect ICP harness connector. Check DTCs. Key off. Did DTC P1280 appear? vehicle. CLEAR DTCs GO to DC10. DC10 CHECK FOR SHORT TO POWER Install breakout box; leave PCM disconnected. Measure resistance between PCM test pin 87 and PCM test pins 55, 71, 90 and 97. GO to DC11. REPAIR short to power in signal circuit 812 (DB/LG). RESTORE vehicle. CLEAR DTCs DC11 CHECK FOR SHORT ON PIN 87 Connect PCM to breakout box. Measure resistance between PCM test pin 87 and PCM test pins 55, 71, 90 and 97. vehicle. CLEAR DTCs INSTALL a new PCM. RESTORE vehicle. CLEAR DTCs DC12 KOEO DIAGNOSTIC TROUBLE CODE (DTC) P1210 DTC P1210 indicates ICP signal voltage was greater than expected during KOEO On- Demand Self Test.
Possible causes: biased ICP sensor open ICP signal return signal circuit shorted to power damaged PCM Disconnect ICP sensor harness connector. Measure resistance between signal return circuit 359 (GY/RD) pin A and ground. GO to DC13. REPAIR open in signal return circuit 359 (GY/RD). RESTORE vehicle. CLEAR DTCs DC13 CHECK SIGNAL CIRCUIT SHORT TO POWER Measure resistance between ICP signal circuit pin C and ground. Key off. Was voltage less than 0.25 V? GO to DC14. REPAIR short to power in ICP signal circuit. RESTORE vehicle. CLEAR DTCs and RETEST. DC14 ICP SENSOR CHECK Connect ICP sensor harness connector. Access ICP PID. Is ICP reading 0 kpa (0 psi)? INSTALL a new PCM. RESTORE vehicle. CLEAR DTCs vehicle. CLEAR DTCs