Replace the Engine/Injector Wiring Harness Assembly for C-15 Petroleum Engine

CAT P/N 237-7595, 242-7248, and 122-1486
Figure 1.1 - Engine/Injector Harness (C-15)

#Remove/Install Procedures:
Figure 1.2 - Harness Wiring Engine/ECM (Before)

CAT 237-7595, and 242-7248
1). Disconnect the negative Battery terminal at the Battery.
2). Loosen allen head screw, and disconnect harness assembly from the ECM (J2/P2 and J1/P1 ECM connectors).
3). Remove all Clip (ladder) and Strap-cable.
4). Remove all Engine sensors connectors: Oil Pressure Sensor, Atmospheric Pressure Sensor, Fuel Pressure Sensor, Fuel Temperature Sensor, Inlet Air Temperature Sensor, Inlet Manifold/Boost Pressure Sensor, Secondary Speed/Timing Sensor, Primary Speed/Timing Sensor, and Coolant Temperature Sensor.
5). Remove P61 Customer connector, and P300 Unit Injector connector.
Figure 1.3 - Harness Wiring Engine/ECM (After)
6). Install new Harness wiring Engine/ECM assembly.

CAT 122-1486
1). Remove Cover valve mechanism group.
Figure 1.4 - Cover valve Mechanism
→Loosen all fastener bolts.
2). Remove Base-valve mechanism cover and Injector harness group.
Figure 1.4 - Base-valve Mechanism Cover
→Loosen all bolts.
→Remove all Cap connector (Unit Injector).
Figure 1.5 - Valve mechanism and Injector Unit
→Remove all Clip, Mounting-Cable tie, and Strap-cable. 
→Remove Harness wiring assembly (Electronic unit Injector).
Figure 1.6 - Base-valve cover and Injector harness
3). Install new Injector harness assembly, and the Base-valve mechanism cover.
4). Connect the Battery system, and access the Injector Solenoid Test through CAT ET software. Read More: Injector Solenoid Test using Caterpillar ET Software.
Figure 1.7 - Injector Solenoid Test
5). Install the Cover valve mechanism.
6). Starts the Engine.

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1 Response to "Replace the Engine/Injector Wiring Harness Assembly for C-15 Petroleum Engine "

  1. Great article on replacing the engine injector wiring harness assembly! I found the steps for removing the old harness and installing the new one to be very clear and concise. The tip about disconnecting the negative battery terminal before starting was also very helpful.
    If you have any needs of electronic components, try