Looking for the best in aesthetics, weight savings and reliability out of your harness?  Our Pro Series harness completely replaces your old OEM harness so you can forget about those electrical gremlins.

This Wiring Specialties PRO Series harness was designed from the ground-up to exceed OEM specifications for wire quality, power/ground routing. With our optimized and 'tucked' approach the end result will be a clean and worry free installation with a guaranteed start up​.​

This harness is specifically engineered for a BMW E36 (1991-1999) with the S13 SR20DET engine swap. It was developed in house on an actual S13 SR20DET engine in a BMW E36 chassis to ensure a perfect fit to all engine connections.

Wiring Specialties offers a number of options for common performance upgrades for this product. Build your perfect harness by selecting from the available options to the right, and as always - if you have any questions, please reach out to us.

ENGINE: S13 SR20DET

• Any SR20DET RWD from JDM S13 Silvia 1988-1993
  
• Any SR20DET RWD from JDM S13 180sx 1989-1998

CHASSIS: BMW E36 (RHD or LHD)

• Any E36 BMW manufactured in 1992-1999
• Factory Speedometer functions by utilizing the ABS system outputs. As long as this system is properly functional, the speedometer will remain accurate.
  
• Factory Tachometer remains accurate unless number of cylinders changes. Use Dakota Digital SGi-8 if the number of cylinders has changed from factory.
• For proper factory engine temp gauge functionality a BMW E36 ECT sensor must be installed into the coolant sensor housing. Harness connection will be provided at the OEM SR20 Gauge temp sender location by the TPS. BMW sensor - BOSCH Part# 0280130026
• Factory Oil Pressure gauge use will require installing the original BMW sensor onto the new engine. Harness connection will be provided at the OEM SR20 Gauge Oil Press sender location by the oil filter.  
• A/C wiring utilizes stock BMW fuse box AC relay and wiring. The AC compressor connector must be wired to the chassis’ output AC signal wire.
  
• Retains functional alternator charge light, reverse lights and wipers.
  

PRO-SERIES HARNESS TECHNICAL SPECS

• Plug and Play – simple and efficient
• NO CORE HARNESS or additional wiring required
• OEM wire colors used, where applicable
• Fireproof fiberglass sleeving used in high-temp sections near the manifold & turbo (-40°C/-40°F to +450°C/+845°F operating temperature)
• Point-to-Point continuity tested on every wire
• Constructed using exact OEM connectors and seals
• Made with high temp TXL wire with adhesive shrink tubing (-40°C/-40°F to +125°C/+257°F operating temperature)
• Wrapped in lightweight nylon loom (-94°C/-137°F to +125°C/+257°F operating temperature)
• Includes a charge harness and improved grounds
• Fully tested after production for an easy plug-and-play installation

PRO-SERIES HARNESS INCLUDES

• Main Engine and Transmission one-piece tucked harness
• Alternator charge cable
• Knock sensor connector
• MAFS connector (OEM or Upgraded)
• VTC connector (for S14 and S15 models)
• Boost solenoid connector
• TPS Connector
• 4x Injector connections
• CAM sensor connector
• 4-pin and 5-pin ignitor chip connectors
• OEM Oxygen sensor connector (wideband wiring is not part of the EFI harness and needs to be supplied)
• Ground ring terminal
• Idle control/fast idle connectors
• Engine coolant sensor and gauge coolant temp switch
• Reverse sensor connector
• Speed sensor connector (Both S13 and S14 connectors are supplied)
• Alternator connector
• Starter signal connector
• OEM oil pressure 1-pin connector (only 1-pin version supplied)
• Nissan Diagnostics connector
• Dash and fuse box connections through the Interface harness
• Printable install instructions with pictures
• Turn Key ENGINE START Guarantee
• Tech support for our customers 7 days a week 

AFTERMARKET ECU DETAILS

• If you are running an aftermarket ECU, we can customize your PRO harness to fit your exact build requirements. Click HERE to download and submit the ECU / Build details form with your order, or we will contact you once the order is placed to collect the needed details.
  
• AEM Infinity, Link and ECU Masters products (and some other standalone ECUs) are able to process a wideband signal input wired DIRECTLY to the ECU. The LSU 4.2 Version of the WB O2 Sensor SHOULD be used, as per AEM and ECU Masters. Select the Oval or Rectangular connector style in the options to match your WB O2 connector.
• All ECUs that are unable to process a wideband signal directly, will be wired for a FACTORY O2 sensor and a labeled flying lead will be provided to connect the ECU to the Wideband controller. For ECUs that do not process a raw wideband signal, a controller must be used. Controllers like an AEM UEGO Gauge Kit or the Haltech CAN wideband unit should be used.
• AEM Infinity, Motec, Link and ECU Masters harnesses are pre-wired for Oil Pressure, Fuel pressure, Oil Temp, IAT and MAP sensor wiring directly to the ECU.   Flex Fuel support is available if desired.   ECU control of a Boost Control Solenoid is also available on most harnesses.
• Apex’i PFC conversions ONLY include the IAT sensor in the main harness. The MAP sensor is wired separately, from the PFC box directly to the sensor. MAP sensor harness should be purchased with the PFC.

FAQ & OTHER DETAILS

• Alternator Charge Cable - This item ties the starter/battery directly to the Alternator output, which allows the improved power routing on our harness to eliminate the wire running from the alternator to the fusebox and/or battery while still charging the battery normally.
• ECU Patch Harness - This optional item eliminates the need to cut into your engine harness for accessories. Use the length of wire provided between the wiring harness plug and the ECU itself to install accessories such as air-fuel meters & controllers, electric boost controllers, rev/speed meters and more.
• Grounding Kit - Our Kit ties a number if engine components to the body of the car and ensures that you will not have issues resulting from poor grounds. The Grounding Kit utilizes Ultra High temp fiberglass sleeving to allow installation under or around exhaust components. Very flexible mounting options allow you to connect the block, head, battery tray, alternator case and chassis to completely eliminate all grounding issues.
• Speedo / Tach Signal Conditioning - The Dakota Digital SGI-5 unit for Speed and the SGI-8 unit for Tach can 'condition' the signal to compensate for cross-platform swaps and/or changes to the number of cylinders. If the Option exists to ADD either unit on the harness page for your swap, then you need them for proper speedo & tach operation. Please note that some transmissions (350z, BMW ZF and S15 Silvia for example) do not have a speed sensor and will require a non-harness based solution like a GPS speedo. Most Nissan to Nissan swaps can simply adjust the tachometer to compensate.
• Plug-n-Play vs Universal - Plug-n-Play harnesses connect to your car's underhood fuse box for power and to connectors under the dash for gauges etc. Universal harnesses do not need an underhood fusebox to connect to and the wiring for gauges and warning lights is provided as a 'flying lead' which are bare wires labeled with their function.
• Right Hand Drive (RHD) Conversions - If you used ALL the stock LHD chassis connectors for your RHD swap, order the LHD version of the harness. If you used ALL the clip/swap RHD chassis connectors, order the RHD version of the harness. If you used a combination of LHD and RHD chassis connectors, please contact us as our harnesses will need modification.
• Don't See It? - If you have injectors, throttle body, coilpacks or any other item that you do not see on the Options offerings, please contact us. Chances are we can do it!
• Battery Cables / Battery Relocation - The battery must be connected to the starter, so you need a battery cable from the positive battery terminal to the starter main power lug. Typically this positive battery cable also powers up the main under hood fusebox, which runs many of the non-engine items on your car like interior lights, dash power and headlights/taillights. Please make sure you have prepared for this as each install is different.
• LS2/LQ9 GM V8 Coil Pack Conversions - We offer an upgrade to the GM V8 LS2/LQ9 Smart Coils on most of our harnesses. This will eliminate the ignitor chip completely (when present), and allow you to use the high performance LS2/LQ9 Coil Packs which are easy to find. Install on JZ or RB engines keeps the coilpacks in their original location over the spark plug with the use of a mounting kit from MOJO Performance. The kits include brackets, mounting hardware, rubber boots and contact springs and can be added to your order by selecting them from the Options list to the right. Install on other engines will require a custom mounting solution and extra parts - please contact us for details. NOTE: OEM Toyota JZ ECUs require an IGF signal produced by the ignitor chip. When the chip is removed for LS2/LQ9 coil upgrade, an aftermarket ECU or IGF simulator box is required (not included with our harness), and the coils will be fired sequentially.