To Place an Order: 
Call 602-909-1961

Business Hours:
Monday-Thursday 9am-5pm 




Cat Conversion Harnesses

$775.00 to $850.00 for most trucks 10 1/2 feet long

These harnesses are used to replace mechanical engines with electronic engines. Each wire is color coded with eleven colors to match the Caterpillar wiring schematic. Each wire is printed every six inches identifying what circuit it is, such as Check Engine Lamp, Stop Engine Lamp, Sensor Common. These harnesses are made from the Caterpillar recommended wire gauge and wire type. Each harness is made to order with the circuits that you specify. Unsure about how you would like your harness configured? We are happy to advise and guide you through the decision. We are not just a manufacturer of wiring harnesses; we are the experts when it comes to Cat conversions.

Each harness comes with the following:
Rubber grommet to route the wiring harness from the engine compartment into cab.
• Check Engine Lamp. Stop Engine Lamp. 
• Data link connector with cap. 
• Weather tight bus used for all sensor common wiring. 
• Fused junction for ignition supply. 
• Sealed fuse holders and fuses for unswitched battery inputs.
• Throttle connector and vehicle speed connectors. 
• High temperature split loom. 
• Installation guide and wiring schematic. 
• Technical support needed to get the job done right.


Cat Bypass Harnesses

A Cat bypass harness is used to communicate with the ECM on or off the engine. Use this harness to run the engine in or out of the truck. The harness is used to bypass the vehicle wiring to the engine ECM. 

Cat 70 Pin
Cat Bypass Harness 70 pin ECM with J1939

Cat Bypass Harness 40 Pin ECM
Cat Perkins 4-4 6-6
Cat/Perkins Bypass Harness 4.4 6.6

Cat 3054E/3056E
Cat 3054E/3056E Bypass Harness ​31 Pin Connector
Cat 3054E/3056E 71 pin
Cat 3054E/3056E Bypass Harness ​70 Pin Connector


Cat Adapters

Wiring harness adapters are used when one electronic Cat engine is being replaced with another electronic Cat engine.

Cat 40 to 70 HD
Cat Heavy Duty Adapter
40 pin truck to 70 pin engine 

Cat 70 to 40 HD
Cat Heavy Duty Adapter
70 pin truck to 40 pin engine

CAT_70 pin truck-40 pin engine fan override
Cat Heavy Duty Adapter
70 pin truck to 40 pin engine with fan override*

Cat 40 to 70 Medium
Cat Medium Duty (3126-C7) Adapter
40 pin truck to 70 pin engine 

Cat 2YG to 40 pin Adapter
Cat 2YG to 40 pin Adapter
Cat 2YG to 70 pin Adapter
Cat 2YG to 70 pin Adapter
Cat 4CK/7LG to 40 pin Adapter
Cat 4CK/7LG to 40 pin Adapter
Cat 4CK/7LG to 70 pin Adapter
*Peterbilt, Kenworth and Western Star applications

Mawk Industries, Inc. 18145 W. Golden Lane, Waddell, AZ 85355
Business Hours Monday - Thursday 9am-5pm
602-909-1961  |  E:
©2017 Mawk Industries, Inc. All rights reserved