This MX engine fault P0668 document is a diagnostic reference from the 2013 PACCAR MX Diagnostic Service Manual. Published by PACCAR for technicians servicing EPA 2013–compliant MX engines, this guide covers fault code P0668 and its diagnostic procedures. The manual provides mechanics and workshop owners with the structured information needed to identify and resolve internal ECU temperature errors on PACCAR MX–powered trucks.
The MX engine fault P0668 P0668 specifically indicates an internal ECU temperature condition classified as an internal error. This resource is essential for understanding the diagnostic workflow when this code appears in the engine control unit.
Document details and specifications — MX engine fault
| Brand | PACCAR |
| Model coverage | MX Engines (EPA 2013) |
| System/Group | DTCs / MX Engines |
| Publication number | Not specified |
| Year/Revision | 2013 |
| Pages | 1 |
| File size | 0.4 MB |
| Format | |
| Language | English |
Table of contents
- Code number P0668
- Fault code description: Internal ECU temperature – Internal error
- Fault code information
- Description of component(s)
- Location of component(s)
- Diagnostic condition
- Set condition of fault code
- Reset condition of fault code
- Electrical diagram(s)
- Technical data
- Possible causes
- Additional information
- Diagnostic Step-by-Step
- Verification Drive Cycle
Applies to these models
This manual applies to trucks equipped with PACCAR MX engines compliant with EPA 2013 emissions standards. Technicians working on PACCAR medium- and heavy-duty commercial vehicles will reference this engine fault P0668 document when P0668 appears on the diagnostic scanner. For official PACCAR support and product information, visit PACCAR official website.
Who needs this engine fault P0668 manual
Diesel mechanics and workshop owners servicing PACCAR MX–powered trucks require this engine fault P0668 guide to diagnose and troubleshoot internal ECU temperature errors. The structured diagnostic approach—covering component description, diagnostic conditions, set and reset procedures, electrical diagrams, and step-by-step verification—supports efficient fault resolution in the shop.
The complete engine fault P0668 PDF is available in the DiagTechPro manuals library. A free account is required to download this one-page diagnostic reference.
Related manuals library
