One of the most significant things an installer can do to speed the conversion process along and keep the headaches at bay is to have their factory GM harness simplified and modified. Novak has gotten this wiring process and PCM programming down to a science.
Typically, the conversion installer will get the factory engine harness from the donor vehicle. This will include every wire and connector between the PCM and the engine's sensors (Oxygen, Throttle Position, Crank Position, etc.) and the active systems (coil triggers, injectors, IAC, etc.).
Novak can simplify this harness, removing unnecessary circuits, consolidating circuits, rerouting and labelling for a simpler 5-6 wire hookup into any Jeep.
This sensor will allow you to run a conventional cable drive speedometer and send critical speed data to your GM PCM for proper powertrain operation.
Pictured left is the extra heavy duty relay used in our rebuilds for radiator fan control.
GM Generation 3+ PCM's come in three major styles as follows:
The early Generation III PCM, 1997 to 1998
The late Generation III PCM, 1999 to mid-2007
The Generation IV PCM w/transmission controller, 2005-present
Make sure your PCM and harness are compatible, if they were not pulled from the same vehicle. Intermixing PCM's and harness can yield unexpected results. Always consult us on this before moving forward.
Since there are variations in every build, we require you contact us via phone or email so we can organize an order to fit your exact needs and help your conversion go as smooth as possible.
Need a cool way to attach your PCM to your Jeep? Our PCM mounting bracket assembly is the best thing to come along in this area for some time.
Please see our Contact page, where you'll find our physical address to which you can send your harness and/or computer. When shipping, we recommend you insure your harness for the typical value of a new replacement harness, which is commonly ~$900 and computer for ~$250. We will associate your order number with your harness/computer when they arrive.
Please do not send anything other than the harness with your shipment. We do not need the throttle pedal, fuse box, battery terminals, or any other sub harnesses, just the engine wiring harness. If you are not sure if it is part of the engine or GM chassis harness, send it and we'll discard as necessary.
Please note that if your PCM or its wires are damaged or in need of repair before it can be used, you may incur an up-charge for the additional labor.
Please contact our sales staff for accurate lead times.
Disclaimer: Any modifications to the Novak harness as provided, without the express written permission of Novak, will void the warranty. This includes any cutting of wires, modification of lengths, or changes to connectors - even if they are part of non-utilized circuits such as unused emissions, evap, or other features. If these are unused in your situation, leave them intact and tie them securely against the harness