1UZ-FE Conversion Wire Harness

In order to provide you the highest quality wire harness available for your swap, Northwest Toys has partnered with the team at Offroad Solutions to provide our exclusive swap wire harness for your build. They are designed to be as close to "plug and play" as possible and work with all the OEM factory connectors with very limited splicing of wires required. When you want the best option available for your build this is it! This colaboration with Off Road Solutions has allowed us to have the best wiring harnesses in the industry!

1UZ-FE Conversion Wire Harness
It is important to read full product description before ordering:

The 1UZ 4.0L fuel injection system is entirely different from that of the older Toyotas. This means the 1UZ electronics and circuit will have to be installed in your older vehicle in order to make this engine swap possible. The NWT 1UZ Conversion Wiring Harness will provide the donor vehicle engine and transmission control circuits in your older vehicle for use with the new Toyota engine computer and components.

From the factory, there are 2 primary parts of the OEM 1UZ fuel injection wiring circuit. The first is the engine wiring harness. This is the harness that is primarily attached to the engine. This is sometimes called the injector harness. This harness connects the engine components such as the fuel injectors, ignition coils, air flow meter, etc. to the engine computer (ECU) and the body harness.

The second part of the 1UZ electronic fuel injection circuit is built into the body wiring, along with the rest of the vehicle’s circuits. The body wiring includes the “under-dash” harness, the engine-bay harness (including fuse box), and even the wiring to the rear. About 40% of the 1UZ fuel injection’s wiring circuit is contained in this harness.

We offer our 1UZ Conversion wiring in 2 main formats:

• Our 1UZ Conversion Adapter Harness is designed for applications that have a used, good-condition, intact engine wire harness from the donor vehicle. Our Conversion Adapter Harness will connect directly to the engine wire harness and the ECU, and works along with the donor engine wire harness to fully complete the engine wiring circuit. Note: The Adapter Format of our conversion harness will not work with “JDM” engine wiring (from Japanese Domestic Market); our Engine wiring format is recommended with JDM donor engines. Once again, the Adapter version requires the use of donor engine wiring that is intact and in good condition; from a North-American-based donor vehicle
  
• Our 1UZ Conversion Engine Wire Harness completely replaces the engine wire harness while also providing the portion of donor engine circuit originally in the body wiring. This harness is a combination of an engine wire harness and an adapter harness and houses 100% of the 1UZ engine circuit in one all-new piece. It is intended for situations when the donor engine wiring is missing, cut or in poor condition. It also works well for JDM import engines since the JDM engine wiring is hard to use in a LHD application.

We also accommodate 2 main recipient vehicle types:

• Our 22R-E/3VZ-E Vehicle option is for ’85-’95 Truck/4Runner and ’93-’94 T100 vehicles that originally had the 3.0L 3VZ-E engine or the fuel injected 22R-E. This version requires that the original body wiring and fuse box is still in place and will plug directly into the body wiring for a simple install. Very little splicing is required to install this version; it is nearly 100% plug-and-play. The original wiring in your older Toyota will not have to be torn apart, and this version will accommodate your OEM gauges (tachometer will require some additional work during the install), speed sensor, reverse lights, 4×4 system and 4×4 indicator lamp.
  
• Our Stand-Alone version is designed for virtually any other vehicle. It works well with carbureted vehicles, other makes, and some race/custom vehicles. This version requires that the vehicle has at least a basic electrical system already in place. This basic system must include: start and ignition switch, charging, fuse/battery and gauge circuits. This will connect to the recipient vehicle through a few simple splices. Note that the Stand-Alone version includes a fuel pump power/control circuit.

We offer 2 options regarding the transmission:

• Manual Transmission: Use this option when using a manual transmission. This includes a case where the donor or recipient vehicle was originally auto and the engine setup will now be manual.
  
• Automatic Transmission: Use this option when using a Toyota automatic transmission. This includes a case where the recipient was originally manual but is now being converted to an automatic transmission. Like the engine circuit, the transmission control circuit was originally split between the body and engine wiring. The Adapter format will include the portion of the transmission control circuit originally placed in the body wiring and the Engine Wire Harness format will include all-new transmission connections.

This product is built per order, please allow 8-10 weeks for order completion. This time can vary by season, if completion time is crucial, please contact NWT before ordering.

Notice when ordering: Please include the following information in the “Order Notes” when placing your order.

From Donor Vehicle:

• VIN, only if 100% certain of engine origin, OR part numbers requested below
• Toyota ECU part number (8966x-xxxxx)
• For Adapter Harness version: Toyota engine harness part number (82121-xxxxx), this is found on a paper tag near the ECU connections.
• Model Year
• Model
• 4WD or 2WD
• Manual or Automatic Transmission
• Will EGR system be used or deleted?

From Your Vehicle:

• For 3VZ-E/22R-E type: VIN - please send photo of VIN tag for 1990 and older models
• RH Drive or LH Drive
• Year Model
• Model
• Original Engine
• Manual or Automatic Transmission (originally)
• Indicate specific transmission to be used in conversion
• Shifter to be used (for A/T models)
• 4WD or 2WD
• If 4×4, indicate transfer case application, original to transmission or changed
• Front suspension type (original or modified)
• For 89-95 Truck, 90-95 4Runner, Indicate if ADD (Auto-Hub) system is in use
• Swapped battery location
• OEM (original-type) tachometer in use?
• Cruise Control in use?
• Oil pressure gauge or light in use?
• For Stand-Alone: fuel pump type and location
• For Stand-Alone: ECU Location
• For Stand-Alone: speedometer type

*****NOTICE TO CUSTOMER: If there is a problem suspected with the wiring harness, call NWT. DO NOT cut, alter, or dissect the ORS conversion harness. NWT accepts no responsibility for a harness that has been tampered with – NO EXCETPIONS.

1) This conversion harness will also require the use of the main 1UZ-FE engine harness, and the sub-harnesses that lead to the ignition coils, alternator and air conditioning.
2) Be sure the 1UZ engine wiring harness is properly installed on the engine and all connectors are plugged in. We highly recommend wrapping the harness with heat tape or exhaust wrap anywhere the harness passes close to the exhaust.
3) Be sure the wiring harness is free and clear of exhaust parts to prevent heat damage.
4) Route the engine harness main loom (under hood) toward the passenger side. If possible, we recommend routing this harness in front of the fuel and brake lines, under the clutch hose and behind the original evaporative canister. The canister firewall mount is a good location to secure this main loom to the firewall using routing clamps.


5) Route the engine wiring harness through the RH side firewall and down to the kick-panel. Connect the ECU connectors to the ECU and lay the ECU in the RH kick-panel area.
6) Lay the ORS conversion harness near the RH kick-panel. Orient the harness so that the leads are pointing in the proper direction.



7) Route the diagnostic lead under the dashboard to the LH side of the vehicle. Find a suitable location below the dashboard panel and secure the diagnostic connector. This connector serves as a port for diagnostic functions.
8) Route all other leads out the RH firewall into the engine bay.
9) Connect the ORS harness ECU connector(s) to the ECU.
10) Connect the ORS harness to the 1UZ-FE engine wiring harness (1 or 2 connectors). Secure the latch on the top of the connector(s), if applicable. 11) Connect the ORS harness to the vehicle body wiring harness. These are the 2 connectors found in the RH side kick-panel that originally connected to the 3VZ-E or 22R-E engine wiring harness.
12) Mount the ORS fuse holders and relays in a suitable location in the RH interior area. Connect the ground lead to a suitable body ground point, preferably an existing ground bolt.
13) If applicable, connect the ORS harness to the Fuel Pump ECU and mount this ECU in the RH interior area.
14) Mount the 1UZ-FE ECU. The brackets bolted to the side of the ECU share the same bolt pattern as all Toyota ECU’s. This allows the installer to share brackets from any ECU to help in the mounting process. Find a location in the passenger side interior that will house the ECU. Be sure that the ORS wiring harness and the 1UZ-FE engine wiring harness leads will reach the ECU and plug in. If the vehicle does not have A/C it is possible to mount the ECU behind the glove box.
15) Route the transfer case (and sometimes reverse light, oxygen sensor, speed sensor) leads (under the hood now) under the RH side of the vehicle. Using routing clamps and/or zip ties, secure the harness to the firewall and metal lines a safe distance from the exhaust.
16) If the ORS harness has 2 leads labeled “reverse light S/W”, cut and splice these wires into the reverse light switch on the side of the transmission. This switch is non-directional, meaning each wire has no specific match.
17) If applicable, cut and splice the leads labeled “transfer case 4WD light S/W” into the transfer case position switch. This switch is also non-directional. Be sure that all connections are secure and sealed.
18) If applicable, connect the lead labeled ‘speed sensor’ to the electronic speed sensor on the transfer case or back of transmission (2WD).
19) If applicable, route the ‘Fuel Pump’ leads to the fuel pump and splice as labeled.
20) Route the Sub-O2 sensor leads to the sub-O2 sensors and connect to each sensor. Secure the Sub-O2 sensor wire leads.
21) Route the Battery fused leads across the top rail of the firewall and down the LH fender area to the battery. Connect the connector to the A/C sub-harness as labeled on the LH side of the engine.
22) Mount the fuse-holders near the battery; do not connect to the battery until the installation is finished.
23) Locate the connector labeled ‘to engine sub-harness connection’. Connect this connector to the corresponding connection on the LH side of the 1UZ engine wire harness. ALTERNATOR WIRING
24) There are 2 ways to wire the alternator. FIRST METHOD (RECOMMENDED)
25) If it was purchased, connect the ORS sub-harness to the Toyota wire harness on the LH side of the engine.
26) Cut the alternator connector from the Truck/4Runner vehicle’s original alternator connection. Splice the ORS sub harness leads to the vehicle’s alternator leads, as labeled.
27) Connect the vehicle’s alternator cable to the 1UZ-FE alternator cable on the LH side of the engine. One method is to simply connect the 2 eyelets using a bolt and nut. In this case, be sure to insulate this connection well. This can also be done w/ a splice connection.
SECOND METHOD
28) Cut the connector from the Truck/4Runner vehicle’s alternator connection. Extend the 3 wires to the 1UZ-FE alternator. If the connector is the same, splice the Truck/4Runner connector back into the wires in the same order.
29) If the connector is different, cut the connector from the 1UZ-FE alternator. Splice the 1UZ alternator to the truck’s wire leads, using the chart below:

Truck/4Runner 1UZ-FE
Yellow wire----------------------------Yellow wire
Red wire--------------------------------Black/yellow wire
White wire------------------------------White/blue wire

30) Connect the vehicle’s alternator cable to the 1UZ-FE alternator cable on the LH side of the engine. One method is to simply connect the 2 eyelets using a bolt and nut. In this case be sure to insulate this connection well. This can also be done w/ a splice connection.
31) Find the power supply wire from the original fuse box, near the original battery location. This wire previously connected to the battery positive terminal. ORS offers an extension cable for this step, ORS-EC047. Using the ORS cable or 8-gauge cable, extend this power lead to reach the new battery location. If not using the ORS lead, be sure to install a fusible link of appropriate size at the end of this cable. Connect this lead to the battery positive terminal.
32) Be sure the power supply wire that is routed in front of the radiator is loomed and properly secured below the radiator support. Excessive contact with the radiator when hot can damage this wiring. Use insulation or further fastening where necessary to prevent excessive contact with the radiator. 33) Important: If this step is not performed before engine is started, oil gauge damage may occur. Some 1UZ-FE engines come standard with an oil pressure switch to operate a light on the dash. Many older vehicles had a gauge on the dash, which used an oil sender. If the original vehicle has a gauge, replace the oil switch on the engine with the oil sender from the original (22R or 3.0L work) engine - it is a direct swap.
34) Go through all wiring and be sure that all wires are routed properly and securely fastened. Be sure that all wires are clear of exhaust parts, engine parts, and sharp edges.
35) Connect the fused leads to the battery positive terminal.