This Cummins ISB accelerator sensor document is a 5-page troubleshooting guide for Fault Code 387 on ISB CM550 engines. It explains the accelerator position sensor circuit, connector inspections, harness resistance checks, ECM voltage checks, and final fault-code clearing steps. The file is intended for workshop diagnosis of an active or inactive accelerator signal fault.
Official Cummins ISB accelerator sensor document details
| Brand | Cummins |
|---|---|
| Model coverage | ISB CM550 (1990-94) |
| System/Group | DTCs; Accelerator Position Sensor Circuit |
| Publication no. | Not shown in the extract |
| Year/Revision | Unknown; document extract shows Copywrite 2017 |
| Pages | 5 |
| File size | 0.4 MB |
| Format | |
| Language | English |
Document table of contents
- Fault Code: 387
- PID: P091 or S232
- SPN: 091 or 620
- FMI: 3 or 1
- Accelerator Position Sensor Circuit
- Description
- Component Location
- Troubleshooting Steps
- Step 1A: accelerator position sensor connector and harness inspection
- Step 1B: read the fault codes using the diagnostic tool
- Step 2A: OEM harness and ECM connector inspection
- Step 2B: open circuit resistance checks between ECM pins and accelerator sensor pins
- Step 2C: short circuit to chassis ground checks
- Step 2D: short circuit from pin to pin checks
- Step 2E: short circuit to a voltage source checks
- Step 3A: ECM 4.75 to 5.25 VDC output check
- Step 4A: verify Fault Code 387 inactive
- Step 4B: clear inactive fault codes using the diagnostic tool
Applicable truck models
This document applies to Cummins ISB CM550 (1990-94) engine diagnostics where Fault Code 387 is set for the accelerator position sensor circuit. The extract identifies the sensor location as the accelerator pedal inside the vehicle cab and references the OEM harness, ECM connector pins 29, 19, and 30, and accelerator position sensor connector pins A, B, and C. For manufacturer information, visit Cummins official website.
Who needs this Cummins ISB accelerator sensor manual
Mechanics, diesel electrical technicians, and workshop owners need this manual when diagnosing accelerator pedal signal faults, 5-VDC supply problems, open circuits, shorts to ground, shorts to voltage, or connector damage on ISB CM550 applications. It supports step-by-step confirmation before replacing the OEM harness, accelerator pedal assembly, accelerator position sensor, or ECM.
The full PDF is available in the DiagTechPro manuals library, free account required to download.
Related manuals library
Sản phẩm liên quan cho hãng này
Cùng brand theo taxonomy hiện có trong catalog WooCommerce.
Cummins Calterm Version 5.16 – Advanced ECM Control and Precision Tuning for Cummins Engines
Cummins INSITE 9.3 – The Essential Diagnostic Tool for Cummins Engines
Cummins InCal CE – The Calibration and Configuration Tool for Cummins Engines
