This CAT C15 04-05 document provides the complete diagnostic procedure for resolving Cylinder #4 Injector Current Low (DTC 0004-05, FMI 73) on Caterpillar C15 on-highway truck engines with MXS serial prefix. It covers ECM-driven fault detection, injector solenoid circuit testing, harness continuity checks, and step-by-step repair verification for open and short circuit conditions across all six cylinders.
Official CAT C15 04-05 document details
| Brand | Caterpillar (CAT) |
| Model coverage | C15 Truck Engine MXS (C15 On-Highway Truck MXS00001-UP) |
| System / Group | Electronic Unit Injector (EUI) Solenoid Circuit — SMCS 1290-038 |
| Publication no. | RENR5088-10 |
| Year / Revision | Published 01/02/2009, Updated 25/02/2009 |
| Pages | 17 |
| File size | 0.3 MB |
| Format | |
| Language | English |
Document table of contents
- 0004-05 Cylinder #4 Injector Current Low (73) — Conditions, System Response, and Initial Test Step
- Injector Solenoid Circuit — Test: System Operation Description
- Cylinder Cutout Test Procedure
- Injector Solenoid Test Procedure (Open / Short diagnosis)
- Electronic Unit Injector Illustration
- Schematic for C15 Engines — P2 ECM Connector Pinout and Valve Cover Connectors
- Test Step 1: Inspect Electrical Connectors and Wiring
- Test Step 3: Check the Variation of the Injectors between Cylinders
- Test Step 5: Check the Harness between the ECM and the Valve Cover Base for an Open Circuit
- Test Step 7: Check the ECM for an Open Circuit (257-8718 Adapter Cable / 120-PIN Breakout)
- Test Step 8: Check the ECM for a Short Circuit
- Short Circuit in Return Line — Resistance Measurement (greater than 10 Ohms expected)
- Injector Code Calibration Reference (DTC 253-02)
Applicable truck models
This procedure applies to Caterpillar C15 on-highway truck engines with configuration prefix MXS00001-UP. The engines use mechanically actuated, electronically controlled Electronic Unit Injectors (EUI) driven by a 105-volt pulse from the Engine Control Module. The diagnostic codes addressed span all six cylinders (DTCs 1-05 through 6-06), covering both injector current low (open circuit) and injector current high (short circuit) faults. The document also references the 257-8718 Adapter Cable Assembly (120-Pin Breakout) for ECM-level testing at the P2/J2 connector. For official Caterpillar parts and service resources, visit Caterpillar Support.
Who needs this CAT C15 04-05 manual
Diesel mechanics and workshop owners diagnosing misfires, low power, or active injector fault codes on C15-powered trucks need this manual. It is essential when Caterpillar Electronic Technician (Cat ET) reports “Open” or “Short” during the Injector Solenoid Test and the automatic Cylinder Cutout Test is disabled by an active code.
The full 17-page PDF is available in the DiagTechPro manuals library; a free account is required to download.
Related manuals library
Sản phẩm liên quan cho hãng này
Cùng brand theo taxonomy hiện có trong catalog WooCommerce.
CAT Perkins Pack – Premium Power & Performance by Caterpillar
CAT SIS
