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PSI
Resource Center
PSI Software Resource Center

Fast access to Software Downloads Encrypted Passwords Plot File Templates Training Resources

Centralized tools, downloads, passwords, and training resources for field technicians.

Software Downloads
Encrypted Passwords
Plot File Templates
Training Resources

System Overview

Software Downloads

cloud_download
Latest

4G Display v684C

Current and most common Diagnostic Software

Note: Older Weichai WP Series may require legacy 4G v608A. Get Legacy v608A
developer_board

GCP Display

Legacy software for products up to 2024

Download
settings

PSI Display

Legacy software out of production since 2018

Download
memory

LCI Display

LCI Series software

Download
usb

ECOM Driver

Required interface driver

Download

lock Encrypted Passwords

4G Display (16 digit)
1BZI-2TOY-EKHF-CHCK
4G Display (26 digit)
DXNGNCZMKTKNE-FMO1N5JEHEBIU
GCP Display
NQUX-VK2M-FF3K-XDCJ
PSI Display
NVWW-ZKMN-NVWK-TDIN
warning Weichai 4G (16 digit)
RBK2-N4KI-JXDO-KDBF
warning Weichai 4G (26 digit)
AI4DGYWO4LCRR-5GCBJQNKGLK0M

show_chart Plot File Templates

4G PSI HD Plot Template v2.2chevron_right 4G Industrial Plot Template v2.2chevron_right Loading and Recording Plotschevron_right Plot File Recording Best Practicechevron_right

school Training Resources

How to install 4G Displayplay_circle How to download ECM Detailsplay_circle How to download ECM Histogramplay_circle Connecting to dual ECMschevron_right

info Knowledge Info

4G Display software update v684Cchevron_right

developer_mode Field Programmer

developer_mode

Field Programmer v6.6.4

ECM calibration updates. Released 1/29/2026

battery_charging_full Lithium Ion Battery

battery_charging_full

iBMS Software v3.1.5

New version released 2/4/2026

Battery Management System software

Download

Diagnostic Software Support

Frequently Asked Questions

You will need an ECOM or ECOM 2 Cable

ECOM Cable part number is z101554

Purchase the ECOM cable from our parts team at parts@psiengines.com or 888-331-5769

Yes, you will need a driver for the diagnostic software.  Luckly, the “ECOM Driver” is contained within the software download .zip folders linked above.  Take a look!

Take a look at the video above for step by step guidance on the installation.

This can occur for several reasons.   See below for the most likely causes.

  1. You are using the incorrect software for the ECM hardware.  Check the white label on the ECM, does it say GCP or 4G?
  2. You are using the incorrect password.
  3. You did not insall the ECOM Driver.
  4. Your engine ECM is not powered  up.

Yes, we offer multiple types of training solutions.  Take a look at our training page as a starting point!