Figure 1. Diagnostic For
The ICP Pressure test should be performed at full load in conjunction with Fuel Pressure Full Load and Boost Pressure Tests. Refer to “11.11 Fuel Pressure Full Load”
. For a reproduction of the applicable portion of the diagnostic form, see Figure above.
The purpose of this test is to determine if the high pressure lube oil system is providing sufficient hydraulic pressure to operate the injectors.
Before connecting the EST tool to the ATA diagnostic connector, turn off all accessories and turn off the ignition.
- Connect the EST (Electronic Service Tool) to the ATA (American Trucking Association) data link connector. See Figure
“ATA Connector Location”
1. ATA Connector
Figure 2. ATA Connector Location
- Press the ↓ key on the EST until NAVPAK™
displays on the screen. Press enter. Press the ↓ key until NAVPAK DATA LIST displays. Press enter. Press the ↓ key until INJ CONTROL PSI displays. See Figure .
Figure 3. Diagnostic For
- Drive the vehicle on the road until the engine reaches operating temperature. Find an open section of road and select a suitable gear. Depress the accelerator pedal (full depression) to the floor, and accelerate to the rated speed and 100% load.
Note: Driving the vehicle uphill or fully loaded will facilitate efforts to reach the proper engine loading at rated engine speed.
- Read ICP pressure (voltage) and record on the diagnostic form.
- Stop the vehicle to read low and high idle ICP pressures (voltage) and record on the diagnostic form.
Alternate Method of Measuring ICP Using Breakout Tee
With a breakout Tee, use the following method to measure the ICP:
- Remove the engine harness connector at the ICP sensor.
- Connect the breakout Tee, J 43102, to the removed engine harness connector and the ICP sensor. See Figure
“Measuring Injection Control Pressure with Breakout Tee”
1. Breakout Tee
2. ICP Sensor
Figure 4. Measuring Injection Control Pressure with Breakout Tee
- Place the DVOM in the cab of the vehicle (if applicable) and connect a set of long leads (+Green, —Black) to the breakout Tee.
- Operate the vehicle under load as follows. Drive the vehicle on the road until the engine reaches operating temperature. Find an open section of road and select a suitable gear. Depress the accelerator pedal (full depression) to the floor, and accelerate to the rated speed and 100% load.
Low injection pressure (voltage) indicates the injectors are not receiving sufficient oil pressure to properly operate the fuel injectors. (Perform the ICP Leakage test.) This may be caused by:
- Defective IPR valve
- Defective high pressure pump
- Injection control pressure (ICP) system leakage
- ECM commanding the IPR valve to reduce injection control pressure due to:
- Low boost pressure
- Incorrect APS (Accelerator Position Sensor) feedback signal
- Incorrect ICP sensor feedback signal.
For ICP diagnostics, refer to “31 Injection Control Pressure Sensor”
. For IPR diagnostics, refer to “34.1 Injection Pressure Regulation System Overview”
|Series 40E Troubleshooting Manual – 6SE241|
|Generated on 10-13-2008|