The H22 is a 2.2L DOHC VTEC engine found in the Honda Prelude that covers many different years and generations of Prelude. This motor is quite common among Honda swap enthusiasts for it’s down low torque and unique power curve.
It’s got a few pros and cons behind the engine swap however, we’ll briefly touch on them here.
- Axles – This can be problematic if you do not opt for custom made axles.
- Cable Transmission – The cable driven shifter and transmission give a vague spongy feel for the shifter, which is a huge contrast vs the rod actuated shifters of the B and D series engines.
- Price – Whether or not you decide on a B series transmission (see below) parts for the H series just aren’t as plentiful as the B, which in turn means higher prices.
While it doesn’t share the same aftermarket support as it’s B series brothers, the H series engine has recently undergone a renaissance with the H2B adapter plate. This adapter plate allows you to bolt on a B series hydro transmission for the absolute best of both worlds.
So without further ado, let’s move onto the ECU pinout for the OBDI 1992-1995 Honda Prelude H22, and the OBDII version of the 97+ Prelude before it’s discontinuation in 2001.
Pin—Color———Desc.
A1—-brn———–Injector #1
A2—-yel———–Injector #4
A3—-red1———Injector #2
A4—-grn/yel——VTEC Solenoid Valve
A5—-blu———–Injector #3
A6—-or/wht——-HO2S heater coil
A7—-grn/blk1—–PGM-FI Main Relay coil
A8—-grn/blk2—–Shorted to A7
A9—-blk/blu——-IAC Valve
A10
A11—-red2——–EGR Control Solenoid
A12—-blu/red—–Condenser Fan Relay
A13—-blu/wht—–MIL
A14
A15—-red/blu—–A/C Clutch Relay
A16—-wht/grn—–Alternator
A17—-pink———IAB Solenoid Valve
A18—-orn/red—–FAS (A/T)
A19—-wht———-Intake Control Solenoid Valve
A20—-red/grn—–EVAP Purge Control Solenoid
A21—-yel/grn1—-ICM
A22—-yel/grn2—-Shorted to A21
A23—-blk1———GND
A24—-blk2———GND
A25—-yel/blk——PGM-FI Main Relay (power)
A26—-blk/red——VTEC Pressure Switch (GND)
B1—-yel/blk——–PGM-FI Main Relay (power)
B2—-brn/blk——-GND
B3—-orn1———-AFSA (A/T)
B4—-pnk———–AFSB (A/T)
B5—-blu/blk——–To A/C Switch
B6
B7—-lt grn———ATP PN Gear Posisiton (A/T)
B8—-red/grn——-PSP Switch
B9—-blu/red——-Starter Cut Relay
B10—orn2———-VSS
B11—orn3———-CYP
B12—wht———–CYP
B13—orn/blu——-TDC
B14—wht/blu——-TDC
B15—blu/grn——-CKP
B16–blu/yel——–CKP
D1—-wht/yel——-Battery
D2—-grn/wht1—–Brake Switch
D3—-red/blu——-KS
D4—-brn/wht——SCS
D5
D6—-lt blu or lt grn-VTEC Pressure Switch
D7—-lt grn/red—-Data Link Connector
D8
D9—-wht/red——ALT
D10—grn/blk——ELD
D11–red/blk——-TP Sensor
D12—wht/blk——EGR Valve Lift Sensor
D13—yel/blu——-ECT Sensor
D14—wht———-HO2S Sense
D15—red/yel——IAT Sensor
D16
D17—wht/blu——MAP Sensor
D18—lt grn/blk—-VREF (A/T)
D19—red/wht——EGR Valve Lift Sensor
D20—yel/wht——TP Sensor
D21—blu/wht——MAP Sensor
D22—grn/wht2—-TP Sensor
OBDII H22a 96+
Layout
A1->A11—-Blank–C1->C10—D1->D5
A12->A24–Blank–C11->C22–D6->D12
A25->A32–Blank–C23->C31–D13->D16
Pin—Color ———Desc.
A1—-yel————Injector #4
A2—-blu————Injector #3
A3—-red————Injector #2
A4—-brn————Injector #1
A5—-orn/blu——-Secondary O2 heater
A6—-blk/wht——-HO2S heater
A7—-orn————EGR Control Solenoid Valve
A8—-grn/yel——-VTEC Solenoid Valve
A9—-brn/blk——-GND (dig)
A10—blk————GND (power)
A11—yel/blk——-PGM-FI Power
A12—blk/blu——-Idle Air Control Valve
A13
A14
A15—red/yel——-Evap Purge Control Solenoid Valve
A16—grn/orn——-Fuel Pump Relay
A17—pnk/blu——-A/C Clutch Relay
A18—gry/red——-MIL
A19—wht/grn——-ALT
A20—yel/grn——–ICM
A21
A22—brn/blk——–GND (dig)
A23—blk————GND (power)
A24—yel/blk——–PGM-FI Power
A25—wht———–Intake Control Solenoid Valve
A26—red/blu——-IAB Control Solenoid Valve
A27—grn———–Radiator Fan Relay
A28—grn/wht——EVAP Bypass Solenoid Valve
A29—orn/grn——Evap control cansiter vent shut valve
A30
A31-
A32-
C1—lt grn/blk——Ref. Voltage for ATTS or TCM (not used)
C2—blu————CKP Detect
C3—grn————TDCP Detect
C4—yel————CKP Detect
C5—blu/orn——-A/C Switch Signal Input
C6—blu/red——-Starter Switch Input
C7—red/wht——-SCS
C8—lt grn ———K Line (scan tool)
C9– –
C10—wht/yel——ECM Backup Power
C11– –
C12—wht———-CKP GND
C13—red———-TDC M Side
C14—blk———-CYP M Side
C15—blu/blk——VTEC Pressure Switch
C16—grn———-P/S Pressure Switch
C17—wht/grn—–ALT Detect signal
C18—blu/wht——VSS Signal
C19 –
C20 – –
C21 – –
C22—brn/yel——IMO Immobilizer Code Signal
C23- –
C24 – –
C25 – –
C26 – –
C27 – –
C28 – –
C29 – –
C30 – –
C31 – –
D1—-red/blk———-TPS Detect
D2—-red/wht———ECT Engine Coolant Temp. Detect
D3—-red/grn———MAP Detect
D4—-yel/red———-Vcc1 (Power for MAP)
D5—-wht/blk———-BKSW Brake Switch Detect
D6—-red/blu———-KS (Knock Sensor Detect)
D7—-wht————–HO2S Detect
D8—-red/yel———-IAT Intake Air Temp Detect
D9—-wht/blk———-EGR Valve Lift Sensor
D10—yel/blu———-Vcc2 (Provides Sensor Voltage)
D11—grn/blk———-SG2 (Sensor Ground)
D12—grn/wht———SG1 (Sensor Ground)
D13- –
D14—wht/red———SHO2S (Secondary O2 Sensor Detect)
D15—wht/blu———PTANK (Detects fuel tank pressure signal)
D16—grn/red———EL (Detects ELD Signal)
Happy tuning!
