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Pcm Inspection: Notes

NOTE:
  • Because the PCM uses a waterproof connector, the inspection for the voltage/wave pattern cannot be performed. The following values are for reference.

Terminal voltage table (Reference) 

G13175466Courtesy of MAZDA MOTORS CORP.

-: Not applicable

Terminal Signal Connected to Test condition Voltage (V) inspection item
1A (1) CAN_2H CAN system related modules Because this terminal is for CAN, integrity determination by terminal voltage is not possible.
  • Related wiring harness
1B (1) CAN_2L CAN system related modules Because this terminal is for CAN, integrity determination by terminal voltage is not possible.
  • Related wiring harness
1C (2) Constant voltage (Vref) Neutral sensor Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
1D Constant voltage (Vref) Engine oil pressure sensor, engine oil temperature sensor, coolant control valve position sensor, refrigerant pressure sensor No. 2 Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
1E Constant voltage (Vref) CKP sensor, revolution sensor Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
1F CKP CKP sensor (See CKP SIGNAL .)
  • CKP sensor
  • Related wiring harness
1G - - - - -
1H(2) Neutral position Neutral sensor Shift lever is at neutral position Below 1.0
  • Neutral sensor
  • Related wiring harness
Shift lever is not at neutral position Approx. 4.5
1I Coolant control valve position Coolant control valve position sensor Because this terminal is for SENT signal, integrity determination by terminal voltage is not possible.
  • Coolant control valve position sensor
  • Related wiring harness
1J Constant voltage (Vref) MAP sensor Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
1K Constant voltage (Vref) Fuel pressure sensor Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
1L Constant voltage (Vref) TP sensor No. 1, TP sensor No. 2 Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
1M A/F A/F sensor Ignition switched ON (engine off) Approx. 5.0
  • A/F sensor
  • Related wiring harness
Idle (after warm up) Approx. 4.1
1N GND Sensor shield Under any condition Approx. 0
  • GND point
  • Related wiring harness
1O TP (No. 1) TP sensor No. 1 Ignition switched ON (engine off) Accelerator pedal released Approx. 1.11
  • TP sensor No. 1
  • Related wiring harness
Accelerator pedal depressed Approx. 4.59
1P - - - - -
1Q IAT (No. 2) IAT sensor No. 2 Ignition switched ON (engine off) IAT 20°C {68°F} Approx. 3.57
  • IAT sensor No. 2
  • Related wiring harness
IAT 40°C {104°F} Approx. 2.70
IAT 60°C {140°F} Approx. 1.87
1R GND TP sensor No. 1, TP sensor No. 2 Under any condition Approx. 0
  • GND point
  • Related wiring harness
1S A/F A/F sensor Idle (after warm up): 0 mA
  • A/F sensor
  • Related wiring harness
1T A/F A/F sensor Idle (after warm up) Approx. 4.1
  • A/F sensor
  • Related wiring harness
1U GND Sensor shield Under any condition Approx. 0
  • GND point
  • Related wiring harness
1V TP (No. 2) TP sensor No. 2 Ignition switched ON (engine off) Accelerator pedal released Approx. 3.92
  • TP sensor No. 2
  • Related wiring harness
Accelerator pedal depressed Below 1.0
1W Fuel pressure Fuel pressure sensor Ignition switched ON (engine off) Approx. 0.57
  • Fuel pressure sensor
  • Related wiring harness
Idle (after warm up) Approx. 1.51
1X MAP MAP sensor Ignition switched ON (engine off) Approx. 4.07
  • MAP sensor
  • Related wiring harness
Idle (after warm up) Approx. 1.37
Racing (Engine speed: 2, 000 rpm) Approx. 0.92
1Y Knocking (+) KS Ignition switched ON (engine off) (Use digital type voltmeter, because measurement voltage will be detected less than true voltage when using analog type voltmeter) Approx. 2.45
  • KS
  • Related wiring harness
1Z Knocking (-) KS Ignition switched ON (engine off) (Use digital type voltmeter, because measurement voltage will be detected less than true voltage when using analog type voltmeter) Below 1.0
  • KS
  • Related wiring harness
1AA - - - - -
1AB GND Neutral sensor (2), ECT sensor No. 1, ECT sensor No. 2, engine oil pressure sensor, engine oil temperature sensor, engine oil level sensor Under any condition Approx. 0
  • GND point
  • Related wiring harness
1AC (2) Revolution Revolution sensor (See REVOLUTION SENSOR SIGNAL .)
  • Revolution sensor
  • Related wiring harness
1AD Electric variable valve timing driver (diagnostic) Electric variable valve timing driver (See ELECTRIC VARIABLE VALVE TIMING DRIVER (DIAGNOSTIC) SIGNAL .)
  • Electric variable valve timing driver
  • Related wiring harness
1AE Ion (No. 2) Ion sensor No. 2 Idle (after warm up) Approx. 4.4
  • Ion sensor No. 2
  • Related wiring harness
1AF Ion (No. 4) Ion sensor No. 4 Idle (after warm up) Approx. 4.4
  • Ion sensor No. 4
  • Related wiring harness
1AG Generator output voltage Generator (See GENERATOR OUTPUT VOLTAGE .)
  • Generator
  • Related wiring harness
1AH ECT ECT sensor No. 1 Ignition switched ON (engine off) ECT 20°C {68°F} Approx. 3.10
  • ECT sensor No. 1
  • Related wiring harness
ECT 40°C {104°F} Approx. 2.16
ECT 60°C {140°F} Approx. 1.40
ECT 80°C {176°F} Approx. 0.87
ECT 100°C {212°F} Approx. 0.54
1AI GND Intake CMP sensor, exhaust CMP sensor Under any condition Approx. 0
  • GND point
  • Related wiring harness
1AJ - - - - -
1AK Ion (No. 3) Ion sensor No. 3 Idle (after warm up) Approx. 4.4
  • Ion sensor No. 3
  • Related wiring harness
1AL Ion (No. 1) Ion sensor No. 1 Idle (after warm up) Approx. 4.4
  • Ion sensor No. 1
  • Related wiring harness
1AM ECT ECT sensor No. 2 Ignition switched ON (engine off) ECT 20°C {68°F} Approx. 3.10
  • ECT sensor No. 2
  • Related wiring harness
ECT 40°C {104°F} Approx. 2.16
ECT 60°C {140°F} Approx. 1.40
ECT 80°C {176°F} Approx. 0.87
ECT 100°C {212°F} Approx. 0.54
1AN Engine oil temperature Engine oil temperature sensor Ignition switched ON (engine off) Approx. 3.21
  • Engine oil temperature sensor
  • Related wiring harness
1AO - - - - -
1AP GND CKP sensor Under any condition Approx. 0
  • GND point
  • Related wiring harness
1AQ - - - - -
1AR - - - - -
1AS Engine oil pressure Engine oil pressure sensor Ignition switched ON (engine off) Below 1.0
  • Engine oil pressure sensor
  • Related wiring harness
Idle (after warm up) 1.07-1.47
1AT GND Sensor shield Under any condition Approx. 0
  • GND point
  • Related wiring harness
1AU Refrigerant pressure (No. 2) Refrigerant pressure sensor No. 2 Refrigerant pressure: 0.17 MPa {1.7 kgf/cm2 , 25 psi} Approx. 0.36
  • Refrigerant pressure sensor No. 2
  • Related wiring harness
Refrigerant pressure: 2.66 MPa {27.1 kgf/cm2 , 3.86 psi} Approx. 3.88
1AV - - - - -
1AW Purge control Purge solenoid valve (See PURGE CONTROL .)
  • Purge solenoid valve
  • Related wiring harness
1AX - - - - -
1AY - - - - -
1AZ (2) Back up light Back up light switch Shift lever is at R position Below 1.0
  • Back up light switch
  • Related wiring harness
Shift lever is not at R position B+
1BA - - - - -
1BB - - - - -
1BC IGT1 Ignition coil No. 1 (See IGT1, IGT2, IGT3, IGT4 CONTROL .)
  • Ignition coil No. 1
  • Related wiring harness
1BD - - - - -
1BE - - - - -
1BF - - - - -
1BG GND Coolant control valve position sensor Under any condition Approx. 0
  • GND point
  • Related wiring harness
1BH GND MAP sensor, IAT sensor No. 2, fuel pressure sensor, refrigerant pressure sensor No. 2 Under any condition Approx. 0
  • GND point
  • Related wiring harness
1BI IGT2 Ignition coil No. 2 (See IGT1, IGT2, IGT3, IGT4 CONTROL .)
  • Ignition coil No. 2
  • Related wiring harness
1BJ - - - - -
1BK - - - - -
1BL - - - - -
1BM Electric variable valve timing motor (rotation pulse) Electric variable valve timing motor (See ELECTRIC VARIABLE VALVE TIMING MOTOR (ROTATION PULSE) SIGNAL .)
  • Electric variable valve timing motor
  • Related wiring harness
1BN Electric variable valve timing motor (rotation direction) Electric variable valve timing motor (See ELECTRIC VARIABLE VALVE TIMING MOTOR (ROTATION DIRECTION) SIGNAL .)
  • Electric variable valve timing motor
  • Related wiring harness
1BO IGT3 Ignition coil No. 3 (See IGT1, IGT2, IGT3, IGT4 CONTROL .)
  • Ignition coil No. 3
  • Related wiring harness
1BP Generator field coil control Generator (See GENERATOR FIELD COIL CONTROL SIGNAL .)
  • Generator
  • Related wiring harness
1BQ - - - - -
1BR GND Sensor shield Under any condition Approx. 0
  • GND point
  • Related wiring harness
1BS - - - - -
1BT Intake CMP Intake CMP sensor (See INTAKE CMP SIGNAL .)
  • Intake CMP sensor
  • Related wiring harness
1BU IGT4 Ignition coil No. 4 (See IGT1, IGT2, IGT3, IGT4 CONTROL .)
  • Ignition coil No. 4
  • Related wiring harness
1BV Electric variable valve timing control Electric variable valve timing driver (See ELECTRIC VARIABLE VALVE TIMING CONTROL SIGNAL .)
  • Electric variable valve timing driver
  • Related wiring harness
1BW - - - - -
1BX - - - - -
1BY - - - - -
1BZ Exhaust CMP Exhaust CMP sensor (See EXHAUST CMP SIGNAL .)
  • Exhaust CMP sensor
  • Related wiring harness
1CA Compressor valve Compressor valve Ignition switched ON (engine off) Approx. 12.22
  • Compressor valve
  • Related wiring harness
Idle (A/C Off) Approx. 14.42
Idle (A/C On) 4.55-5.3
1CB A/F sensor heater control A/F sensor heater (See A/F SENSOR HEATER CONTROL SIGNAL .)
  • A/F sensor heater
  • Related wiring harness
1CC - - - - -
1CD - - - - -
1CE - - - - -
1CF - - - - -
1CG - - - - -
1CH - - - - -
1CI - - - - -
1CJ - - - - -
1CK Engine oil control Engine oil solenoid valve (See ENGINE OIL CONTROL SIGNAL .)
  • Engine oil solenoid valve
  • Related wiring harness
1CL - - - - -
1CM - - - - -
1CN - - - - -
1CO Hydraulic variable valve timing control OCV (See HYDRAULIC VARIABLE VALVE TIMING CONTROL SIGNAL .)
  • OCV
  • Related wiring harness
1CP - - - - -
1CQ Drive-by-wire control (+) Throttle valve actuator (See DRIVE-BY-WIRE CONTROL (+) SIGNAL .)
  • Throttle valve actuator
  • Related wiring harness
1CR Drive-by-wire control (-) Throttle valve actuator Idle (after warm up) Because the drive-by-wire control (-) terminal value varies depending on the vehicle, examination using only the ICQ terminal is not possible. When performing the inspection, perform it together with the ICR terminal.
  • Type A

    - B+

  • Type B

- Approx. 0
  • Throttle valve actuator
  • Related wiring harness
1CS - - - - -
1CT - - - - -
1CU Fuel injection control (+) Fuel injector No. 3 (See FUEL INJECTION CONTROL (+) SIGNAL .)
  • Fuel injector No. 3
  • Related wiring harness
1CV Fuel injection control (-) Fuel injector No. 3 (See FUEL INJECTION CONTROL (-) SIGNAL .)
  • Fuel injector No. 3
  • Related wiring harness
1CW Coolant control valve control (+) Coolant control valve Ignition switched ON (engine off) B+
  • Coolant control valve
  • Related wiring harness
1CX Coolant control valve control (-) Coolant control valve Ignition switched ON (engine off) B+
  • Coolant control valve
  • Related wiring harness
1CY Fuel injection control (+) Fuel injector No. 2 (See FUEL INJECTION CONTROL (+) SIGNAL .)
  • Fuel injector No. 2
  • Related wiring harness
1CZ Fuel injection control (-) Fuel injector No. 2 (See FUEL INJECTION CONTROL (-) SIGNAL .)
  • Fuel injector No. 2
  • Related wiring harness
1DA - - - - -
1DB - - - - -
1DC Fuel injection control (+) Fuel injector No. 4 (See FUEL INJECTION CONTROL (+) SIGNAL .)
  • Fuel injector No. 4
  • Related wiring harness
1DD Fuel injection control (-) Fuel injector No. 4 (See FUEL INJECTION CONTROL (-) SIGNAL .)
  • Fuel injector No. 4
  • Related wiring harness
1DE - - - - -
1DF - - - - -
1DG Fuel injection control (+) Fuel injector No. 1 (See FUEL INJECTION CONTROL (+) SIGNAL .)
  • Fuel injector No. 1
  • Related wiring harness
1DH Fuel injection control (-) Fuel injector No. 1 (See FUEL INJECTION CONTROL (-) SIGNAL .)
  • Fuel injector No. 1
  • Related wiring harness
1DI High pressure fuel pump control (+) High pressure fuel pump (See HIGH PRESSURE FUEL PUMP CONTROL (+) SIGNAL .)
  • High pressure fuel pump
  • Related wiring harness
1DJ High pressure fuel pump control (-) High pressure fuel pump (See HIGH PRESSURE FUEL PUMP CONTROL (-) SIGNAL .)
  • High pressure fuel pump
  • Related wiring harness
2A Battery voltage Battery Ignition switched ON (engine off) B+
  • Related wiring harness
2B Main relay control Main relay Ignition switched ON (engine off) Below 1.0
  • Main relay
  • Related wiring harness
2C - - - - -
2D Fuel pump control Fuel pump control module (See FUEL PUMP CONTROL SIGNAL .)
  • Fuel pump control module
  • Related wiring harness
2E - - - - -
2F Ignition (IG1) IG1 relay No. 1 Ignition switched ON (engine off) B+
  • IG1 relay No. 1
  • Related wiring harness
2G - - - - -
2H Starter cutoff control Starter relay, BCM Ignition switched ON (engine off) MTX
  • Clutch pedal released ATX
  • Selector lever position is not P or N position
 B+
  • Starter relay
  • BCM
  • Related wiring harness
MTX
  • Clutch pedal depressed ATX
  • Selector lever position is P or N position
 Below 1.0
2I - - - - -
2J - - - - -
2K - - - - -
2L - - - - -
2M CAN_3H CAN system related modules Because this terminal is for CAN, integrity determination by terminal voltage is not possible.
  • Related wiring harness
2N CAN_3L CAN system related modules Because this terminal is for CAN, integrity determination by terminal voltage is not possible.
  • Related wiring harness
2O - - - - -
2P Brake (No. 2) Brake switch (No. 2 signal) Brake pedal released Below 1.0
  • Brake switch (No. 2 signal)
  • Related wiring harness
Brake pedal depressed B+
2Q - - - - -
2R Ambient temperature Ambient temperature sensor Ignition switched ON (engine off) AAT 20°C {68°F} Approx. 2.70
  • Ambient temperature sensor
  • Related wiring harness
AAT 30°C {104°F} Approx. 1.80
2S CAN_H CAN system related modules Because this terminal is for CAN, integrity determination by terminal voltage is not possible.
  • Related wiring harness
2T CAN_L CAN system related modules Because this terminal is for CAN, integrity determination by terminal voltage is not possible.
  • Related wiring harness
2U - - - - -
2V - - - - -
2W - - - - -
2X - - - - -
2Y Engine oil level sensor (LIN) Engine oil level sensor Because this terminal is for LIN, good/no good judgment by terminal voltage is not possible.
  • Related wiring harness
2Z - - - - -
2AA - - - - -
2AB - - - - -
2AC - - - - -
2AD - - - - -
2AE - - - - -
2AF A/C cut-off control A/C relay A/C relay OFF B+
  • A/C relay
  • Related wiring harness
A/C relay ON Below 1.0
2AG - - - - -
2AH - - - - -
2AI GND MAF sensor, IAT sensor No. 1, refrigerant pressure sensor No. 1, ambient temperature sensor, clutch stroke sensor (2), fuel tank pressure sensor (3) Under any condition Approx. 0
  • GND point
  • Related wiring harness
2AJ (3) Fuel tank pressure Fuel tank pressure sensor Ignition switched ON (engine off) Approx. 2.6
  • Fuel tank pressure sensor
  • Related wiring harness
2AK - - - - -
2AL (3) CV solenoid control CV solenoid valve Ignition switched ON (engine off) B+
  • CV solenoid valve
  • Related wiring harness
Idle (CV solenoid valve not operating) B+
Idle (CV solenoid valve operating) Below 1.0
2AM Cooling fan control Cooling fan relay No. 1 Cooling fan operating Below 1.0
  • Cooling fan relay No. 2
  • Related wiring harness
Cooling fan not operating B+
2AN - - - - -
2AO Constant voltage (Vref) APP sensor No. 2 Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
2AP (2) Clutch stroke sensor Clutch stroke sensor Clutch pedal depressed Below 1.0
  • Clutch stroke sensor
  • Related wiring harness
Clutch pedal released Approx. 4.5
2AQ - - - - -
2AR - - - - -
2AS Cooling fan control Cooling fan relay No. 2 Cooling fan operating Below 1.0
  • Cooling fan relay No. 2
  • Related wiring harness
Cooling fan not operating B+
2AT Constant voltage (Vref) MAF sensor, IAT sensor No. 1 Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
2AU Constant voltage (Vref) Clutch stroke sensor (2), fuel tank pressure sensor (3) Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
2AV Refrigerant pressure Refrigerant pressure sensor No. 1 Refrigerant pressure: 0.17 MPa {1.7 kgf/cm2 , 25 psi} Approx. 0.36
  • Refrigerant pressure sensor No. 1
  • Related wiring harness
Refrigerant pressure: 2.66 MPa {27.1 kgf/cm2 , 386 psi} Approx. 3.88
2AW Fuel pump control Fuel pump relay Ignition switched ON (engine off) B+
  • Fuel pump relay
  • Related wiring harness
Idle (after warm up) Below 1.0
2AX Fuel pump control module (diagnostic) Fuel pump control module (See FUEL PUMP CONTROL MODULE (DIAGNOSTIC) SIGNAL .)
  • Fuel pump control module
  • Related wiring harness
2AY - - - - -
2AZ Constant voltage (Vref) Refrigerant pressure sensor No. 1 Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
2BA Constant voltage (Vref) APP sensor No. 1 Ignition switched ON (engine off) Approx. 5.0
  • Related wiring harness
2BB APP (No. 2) APP sensor No. 2 Ignition switched ON (engine off) Accelerator pedal released Approx. 0.38
  • APP sensor No. 2
  • Related wiring harness
Accelerator pedal depressed Approx. 2.05
2BC - - - - -
2BD (1) Selector lever position TCM Selector lever position is not P or N position B+
  • TCM
  • Related wiring harness
Selector lever position is P or N position Below 1.0
2BE Intake air MAF sensor, IAT sensor No. 1 Because this terminal is for SENT signal, integrity determination by terminal voltage is not possible.
  • MAF sensor, IAT sensor No. 1
  • Related wiring harness
2BF - - - - -
2BG GND APP sensor No. 2 Under any condition Approx. 0
  • GND point
  • Related wiring harness
2BH GND APP sensor No. 1 Under any condition Approx. 0
  • GND point
  • Related wiring harness
2BI - - - - -
2BJ HO2S heater control HO2S heater (See HO2S HEATER CONTROL SIGNAL .)
  • HO2S heater
  • Related wiring harness
2BK HO2S (+) HO2S Idle (after warm up) Approx. 2.15
  • HO2S
  • Related wiring harness
2BL HO2S (-) HO2S Idle (after warm up) Approx. 2.05
  • HO2S
  • Related wiring harness
2BM GND Sensor shield Under any condition Approx. 0
  • GND point
  • Related wiring harness
2BN APP (No. 1) APP sensor No. 1 Ignition switched ON (engine off) Accelerator pedal released Approx. 0.75
  • APP sensor No. 1
  • Related wiring harness
Accelerator pedal depressed Approx. 4.1
2BO Main power supply Main relay Ignition switched ON (engine off) B+
  • Main relay
  • Related wiring harness
2BP - - - - -
2BQ GND GND Under any condition Approx. 0
  • GND point
  • Related wiring harness
2BR Main power supply Main relay Ignition switched ON (engine off) B+
  • Main relay
  • Related wiring harness
2BS - - - - -
2BT GND GND Under any condition Approx. 0
  • GND point
  • Related wiring harness
(1) ATX
(2) MTX
(3) U.S.A. and Canada specs.
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