Electrical

6 of 6 compatibility entries for Honda

Horn Verified Modification Required

Accord horn (PN: 38100-STK-A02)

Source: Accord
Target: Fit (2nd generation (GE)) - 2009-2013

The Accord horn reuses the Fit's factory 12mm mounting bolt and plugs straight into the stock electrical connector, so it is effectively plug-and-play once the bracket is repositioned. Two punched ridges behind the hood latch act as alignment guides; seat the repositioned bracket between them and the horn sits roughly level. The mounting bolt doubles as the ground path, so the horn will not sound until it is bolted to the chassis. Access requires removing the engine-bay bulkhead cover (eight clips) and the plastic hood-latch cover.

moderate
Climate Control (HVAC) Verified Modification Required

Digital Climate Control (DCC) system

Source: Prelude (4th generation (BB), JDM digital-climate-control-equipped)
Target: Prelude (4th generation (BB), Australian-market manual-climate car)

The DCC controller will not operate on its own. A working install requires the full sensor suite (sunlight, cabin, heater-core, evaporator and outside-air sensors), the air-mix motor, power transistor and blower high relay. Fitting the system means recovering the A/C refrigerant (and, on 1992-1993 R12 cars, converting to R134a), draining the coolant, and removing the dash, evaporator and heater unit. New firewall heater hoses are recommended (Honda 79721550000 short and 79725550010 long). The conversion can be staged: control head and manual fan/vent function first, then the A/C and heater-box work.

difficult
Instrument cluster / EPS indicator Verified Modification Required

EPS warning-light telltale and diagnostic wiring

Source: Civic Hybrid (EM2) - 2003-2005
Target: RSX (DC5) - 2002-2006

Wiring uses the Civic Hybrid EPS control unit Connector C pinout, which matches the EP3 Civic Si per both factory manuals. The LED negative leg ties to C6 YEL/BLU (EPS warning light) and its positive leg is powered from the RSX cluster harness: B7 Yellow on 02-04 cars or B6 Yellow on 05-06 cars, both fed by Fuse 10 under the dash. For diagnostic communication, the brown wire on the back of the DLC is spliced to C8 BRN (service check signal) and the gray wire to C20 GRY (Diagnosis-H). Result is OEM-like behavior: telltale on with ignition, off within about two seconds when no codes are stored, plus the ability to read/clear codes and reset the BCU.

difficult
Engine management (OBD0 to OBD1 conversion) Verified Modification Required

OBD1 ECU (P75) and OBD1 distributor with OBD0-to-OBD1 conversion harness

Source: Integra VTi-R (DC2 (OBD1 era))
Target: CR-X SiR (EF8 (OBD0; procedure applies to any OBD0 Civic/CR-X)) - 1989-1991

Documented conversion of an OBD0 EF8 CR-X to OBD1 using a P75 ECU and an OBD1 distributor from an Integra VTi-R; a DC2 distributor bolted up and worked well. The car ran Crome with a stock 203 ROM for an OBD1 JDM B16A and started on the first attempt. The original single-wire O2 sensor works fine with the heater circuits disabled in the ROM. With this harness the blue 2-pin connector formerly used for setting timing (under the LH dash near the heater blower on EF8/EF9) becomes the SCS connector for OBD1 diagnostics and base-timing adjustment. Base ignition timing must be set with a timing light after conversion. A follow-up member completed the same conversion successfully with the car starting first go.

moderate
Ignition and starting system Verified Modification Required

S2000 engine start button

Source: S2000 (AP1)
Target: Prelude (5th generation) - 1997

Working conversion documented on a 1997 (5th-gen) Prelude. The key barrel, steering lock and factory immobilizer are retained; the key is turned to ON and the button is pressed and held to crank, exactly replicating S2000 operation. The relay schematic transfers to any Honda - a follow-up contributor fitted a JDM Civic Type R start button and panel to a Civic FD as a direct bolt-in using the same diagram (adding pin 1 illumination negative and pin 2 illumination positive), and another contributor wired a button on a DC2 with a simple two-wire hookup at the ignition barrel loom (constant 12 V plus starter wire). With the ignition on, the ENGINE START legend illuminates without the parking lights on; this matches factory S2000 behavior.

moderate
Ignition / Starter switch Verified Modification Required

S2000 push-start (engine start) button

Source: S2000 (AP1/AP2) - 1999-2009
Target: RSX (DC5) - 2002-2006

Nothing bolts up directly. The button functions as a momentary starter trigger, not a full keyless system: the key must still be inserted and turned to ON so the immobilizer is satisfied, and the button only cranks the starter. Required extras are a 12V 30A SPDT 5-pin relay, 16-18 gauge wire, connectors, and a mounting bezel. Plug-and-play harness kits that plug into the back of the button are sold and reduce the amount of tapping required.

moderate