Wiring Harness & PCM Programming Services
for the
GM Generation III+ Engines
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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.
Wiring Harness
Typically, the conversion installer will get the factory engine harness from the donor vehicle. This will include the 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, consolodating circuits, rerouting and labelling for a simpler 5-6 wire hookup into any Jeep.
Harness Mods at a Glance :
- Install DLC port for installation in the Jeep cab
- Provide fuel pump relay and simplified fuel pump circuit
- Provide a simplified and water-tight power distribution center with standard ATC style fuses and relays
- Simplify main 12V and main Ground circuits
- Retain or eliminate rear (post-catalytic) O2 sensors, as requested
- Provide an easy-to-install MIL lamp
- Provide VSS leads
- Fully inspect all circuits
- Optionally, install a standalone air conditioning control circuit
- Eliminate complicated E85 (Flex-Fuel) circuits if requested
- Provision for standard shift or automatic shift (typ. 4L60E) transmissions
- Minorly damaged harnesses can be repaired. For more extensive damage, reasonable additional costs will be determined
- Five wire hookup (manual trans option) or seven wire hookup (automatic trans option)
- Electric fan control circuit and relay can be added, optionally
- Park / Neutral safety switch can be added for Jeeps that originally did not have this circuit
- All trunks and branches are arranged and wrapped with new split-loom and made to more appropriate lengths for your particular vehicle.
Identifying Your GM PCM
GM Generation 3+ PCM's come in three major styles as follows:
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| 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 |
| GM Gen. III + engine control wiring harness modifications. Includes fuse & relay centers, harness simplification, rerouting, testing, labelling, minor repair where necessary and re-looming |
Computer Programming at a Glance:
- Remove Vehicle Anti-Theft (VATS) functions
- Reprogram important speed sensitive functions for tire size and axle ratio
- Remove rear O2 sensors (optionally, if applicable to your laws)
- Remove E85 (Flex-Fuel) complications
- Verify proper computer operation
- Switch from 4L80E to 4L60E (or vica versa) if applicable
- Any desired follow-up programming (up to three times) is included in the original price (shipping costs excluded)
| Programming, Powertrain Control Module, GM. Includes VATS removal, tire size & axle ratio, emissions modifications as requested, and optimization |
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| 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. |
Shipping Instructions
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 Shopping Cart order with your harness/computer when they arrive.
Make sure to let us know your phone number and e-mail address when ordering. The Novak shopping cart will ask for these details. We are likely to call or e-mail you with any questions and confirmations.
Currently, typical turnaround time is under 12 days, plus shipping time as you've chosen (Ground, Third Day, Second Day, etc.)




