OBD1 Pinouts

EDM P06 (D15B7), P28 (D16Z6/D16Z9), P30 (B16A2) and P1G (D15Z3)

On this page the OBD1 sheme’s known to me are presented EDM (Europen Domestic Market) style. The biggest difference between EDM and USDM (United States Domestic Market) is the ELD circuit (Electric Load Detection) that misses and the KS (Knock Sensor). Some connections are only found on P28 and P30 ECU’s. Those are marked coloured red. Some connections are different from car to car. Those are marked grey.

Common OBD1 pinout. This layout is based on European P06, P28 and P30 ECUs for D15B7, D16Z6, D16Z9 and B16A2 engines.

Nomenclature:
ACC –   A/C relay
ACS –   A/C switch
ALTC –  Alternator relay, for control purposes, not present on all ECU’s
ALTF –  Alternator switch
BKSW- Brake switch, for control purposes, not present on all ECU’s
CKP –   Crankshaft position, (P)ulse or (M)ass, gives several pulses (~20?) during each cam shaft rotation
CYP –   Cylinder position, (P)ulse or (M)ass, gives one pulse during each cam shaft rotation
DLC –    Diagnostic connector, communication signal to the 3 wire connector next to the SCS connector
ECO –   Unknown function (is there an ECO light on D15Z3?)
ECT –    Engine coolant temperature
EGR –   Exhaust gas recirculation
EGRL – Unknown function (probably related to EGR)
FANC – Fan relay, for control purposes, not present on all ECU’s
FLR –    Fuel relay, 1 is always present, 2 can be ignored
IACV – Idle air control valve, controls the 2 wire type IACV valve
IAT –     Intake air temperature
ICM –    Ignition pulses, 1 is always present, 2 can be ignored
IGP –    Battery feed, only active when key is turned
INJ –     Injector, the number refers to the cylinder used (1 is on the side with the belts)
LG –      Ground for battery circuit
MAP –   Manifold absolute pressure
MIL –     Motor indication light, this one gives the control engine light (CEL) signal
PCS –   Control solenoid, this one is for the small black cylindric valve on the back of the IM
PG –     Ground for battery circuit
PO2H – Primary oxygen sensor heater, connects with the ground of the car to activate the heater
PO2S – Primary oxygen sensor signal
SCS –   Service connector switch, checks if the SCS connector is hot wired (for reading engine error codes)
SG –     Ground for 5V circuit, 1 is for the MAP sensor, 2 is for the other sensors
STS –    Starter switch
TDC –    Top dead centre, (P)ulse or (M)ass, gives four pulses during each cam shaft rotation
TPS –    Throttle position signal
VBU –   Back up battery feed, always active (unless battery is removed)
VCC –   5V feed, 1 is for the MAP sensor, 2 is for the other sensors
VREF – Unknown function (probably related to wideband oxygen)
VSS –   Vehicle speed sensor
VTM –   Oil pressure switch, only -but not always- present on VTEC equiped vehicles
VTS –    VTEC solenoid, only present on VTEC equiped vehicles

Below I also provided a D15Z3 sheme. Unfortunatly not each function of all pins are known to me. I do know that most question marks are connected to either the EGR (Exhaust Gas Recirculation) and wideband lambda sensor system (Yes this car has a wideband oxygen sensor system normally. However, I do not know the exact possibilities of this sensor). I used the sheme succesfully for a P28 ECU swap once. The wideband lambda wires can be re-used for a normal 4-wire lambda sensor. The VTM pin can be short circuited to the VTS pin to prevent VTEC error codes from the P28 ECU.

The partly unsure sheme of the P1G ECU for the D15Z3 engine.

Please, send any questions and/or remarks to me.

Dodo Bizar

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