Isuzu 4JJ1 User Manual

WORKSHOP MANUAL
ENGINE CONTROL SYSTEM
(4JJ1 model)
No.LG4JJED-WE-0871
WORKSHOP MANUAL
ENGINE CONTROL SYSTEM (4JJ1 model)

Isuzu 4JJ1 Specifications

General

Brand	Isuzu
Model	4JJ1
Category	Control Systems
Language	English

Summary

ENGINE

Engine Control System (4JJ1)

Details the engine control system for the 4JJ1 model, covering its various functions and components.

Specifications

Diagnostic Trouble Code (DTC) List

DTC P0016 (Flash Code 16)

Describes the crankshaft/ camshaft position sensor correlation circuit and diagnostic steps.

Engine Control Module (ECM) Connector End Views

ECM Connector J14 Pin Functions

Details the pin assignments, wire colors, and functions for the ECM J14 connector.

Diagnostic Information and Procedures

Engine Control System Check Sheet

Diagnostic Starting Point - Engine Controls

Scan Tool Output Controls

Fuel Pressure Control

Scan Tool Does Not Power Up

Circuit/ System Testing Scan Tool Does Not Power Up

Provides step-by-step troubleshooting for issues where the scan tool does not power up.

Scan Tool Does Not Communicate with CAN Device (Euro 4 Specification)

Circuit/ System Testing Scan Tool Does Not Communicate with CAN Device (Euro 4 Specification)

Outlines troubleshooting steps for communication loss with the ECM over the CAN link.

Lost Communication with The Engine Control Module (ECM) (Except Euro 4 Specification)

Circuit/ System Testing Lost Communication with The Engine Control Module (ECM) (Except Euro 4 Specification)

Details troubleshooting procedures for lost communication with the ECM via the Keyword serial data link.

Engine Cranks but Does Not Run

Circuit/ System Testing Engine Cranks but Does Not Run

Provides a diagnostic table for identifying causes when the engine cranks but does not start.

DTC P0016 (Flash Code 16)

Circuit/ System Testing DTC P0016

Describes the crankshaft/ camshaft position sensor correlation circuit and diagnostic steps.

Symptoms - Engine Controls

Hard Start

Rough, Unstable, or Incorrect Idle and Stalling

Repair Instructions

Engine Control Module (ECM) Replacement

Service Programming System (SPS)

Explains the SPS for programming control modules, including remote and pass-thru procedures.