Engine Controls - System & Component Testing: Introduction

NOTE: The 4.7L models are equipped with the Next Generation Controller (NGC), which has a PCM and TCM combined into a single controller. The NGC is still referred to as the PCM. The NGC PCM has 4 harness connectors (Black C1, Gray C2, White C3 and Green C4). The 5.9L models are equipped with the Jeep/Truck Engine Controller (JTEC) Powertrain Control Module (PCM) and a separate Transmission Control Module (TCM). The JTEC PCM has 3 harness connectors (Black C1, White C2 and Gray C3).

Before testing separate components or systems, follow proper work flow. See the following:

On 4.7L, see DIAGNOSTIC PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - DURANGO - 4.7L article.
On 5.9L, see DIAGNOSTIC PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - DURANGO - 5.9L article.

If no Diagnostic Trouble Codes (DTC) are present and a no-start condition exists, proceed to NO-START DIAGNOSIS in BASIC DIAGNOSTIC PROCEDURES - DURANGO article. If no DTCs are present and a driveability condition exists, proceed to TROUBLE SHOOTING - NO CODES - DAKOTA & DURANGO article for diagnosis by symptom (i.e., ROUGH IDLE, ENGINE STALLS, etc.).

NOTE: Testing individual components does not isolate possible short or open circuits. Unless stated otherwise in test procedure, perform all voltage tests with a Digital Volt-Ohmmeter (DVOM) having a minimum 10-megohm input impedance. Use ohmmeter to isolate wiring harness short or open circuits.