Engine Control System (L3 with TC): Other Mazda CX-7 I

Without Using the M-MDS

Note. The PCM terminal voltage can vary with the conditions when measuring and changes due to aged deterioration on the vehicle, causing false diagnosis. Therefore determine comprehensively where the malfunction occurs among the input systems, output systems, and the PCM.

PCM terminals

1. 1AE (+)-body ground (-)

Oscilloscope setting

1. 5 V/DIV (Y), 20 ms/DIV (X), DC range

Scheme 54

1. Idle after warm up (no load, P/S off, A/C off)

HO2S (front) heater control signal PCM terminals

1. 2C (+)-body ground (-)

1. 2 V/DIV (Y), 20 ms/DIV (X), DC range

Scheme 55

1. Idle after warm up (no load, P/S off, A/C off)

1. 2S (+)-body ground (-)

1. 2 V/DIV (Y), 100 ms/DIV (X), DC range

Scheme 56

1. Idle after warm up (no load, P/S off, A/C off)

1. 2W (+)-body ground (-)

1. 2 V/DIV (Y), 5 ms/DIV (X), DC range

Scheme 57

1. Idle after warm up (no load, P/S off, A/C off)

1. 2AA (+)-body ground (-)

1. 20 V/DIV (Y), 20 ms/DIV (X), DC range

Scheme 58

1. Ignition switch to the ON position

1. 2AB (+)-body ground (-)

1. 10 V/DIV (Y), 20 ms/DIV (X), DC range

Scheme 59

1. Engine speed is 2,000 rpm

1. 2AF (+)-body ground (-)

1. 2.5 V/DIV (Y), 1 ms/DIV (X), DC range

Scheme 60

1. Idle after warm up (no load, P/S off, A/C off)

1. 2AI (+)-body ground (-)

1. 0.5 V/DIV (Y), 2 ms/DIV (X), DC range

Scheme 61

1. Idle after warm up (engine speed approx. 650 rpm, no load)

1. 2AJ (+)-body ground (-)

1. 2 V/DIV (Y),1 ms/DIV (X), DC range

Scheme 62

1. Idle after warm up (no load, P/S off, A/C off)

1. IGT1 (NO. 1): 2BA (+)-body ground (-)
2. IGT2 (NO. 2): 2AW (+)-body ground (-)
3. IGT3 (NO. 3): 2AX (+)-body ground (-)
4. IGT4 (NO. 4): 2AT (+)-body ground (-)

1. 2 V/DIV (Y), 20 ms/DIV (X), DC range

Scheme 63

1. Idle after warm up (no load, P/S off, A/C off)

1. Fuel injection NO. 1: 2BB (+)-body ground (-)
2. Fuel injection NO. 2: 2BC (+)-body ground (-)
3. Fuel injection NO. 3: 2BD (+)-body ground (-)
4. Fuel injection NO. 4: 2AZ (+)-body ground (-)

1. 10 V/DIV (Y), 20 ms/DIV (X), DC range

Scheme 64

1. Idle after warm up (no load, P/S off, A/C off)

1. Fuel injection NO. 1, NO. 4: 2BG (+)-body ground (-)
2. Fuel injection NO. 2, NO. 3: 2BH (+)-body ground (-)

1. 20 V/DIV (Y), 400 us/DIV (X), DC range

Scheme 65

1. Idle after warm up (no load, P/S off, A/C off)

Using the M-MDS

Note. PIDs for the following parts are not available on this model. Perform the specific inspections for the following parts: CMP sensor (See CAMSHAFT POSITION (CMP) SENSOR INSPECTION[L3 WITH TC] .) Main relay

Scheme 66

1. Connect the M-MDS to the DLC-2.
2. Turn the ignition switch to the ON position.
3. Measure the PID value. If PID value is not within the specification, follow the instructions in the "Inspection item" column. NOTE: The PID/DATA MONITOR function monitors the calculated value of the input/output signals in the PCM. Therefore, an output device malfunction is not directly indicated as a malfunction of the monitored value for the output device. If a monitored value of an output device is out of specification, inspect the monitored value of the input device related to the output control. For input/output signals except those of the monitoring items, use a voltmeter to measure the PCM terminal voltage. The simulation items that are used in the ENGINE CONTROL SYSTEM OPERATION INSPECTION are as follows. ACCS, ALTF, ARPMDES, FAN_DUTY, EVAPCP, FP, FUELPW, GENVDSD, HTR11, HTR12, IMRC, INJ_1, INJ_2, INJ_3, INJ_4, SEGRP, test, VT DUTY1, WGC

PID/DATA MONITOR TABLE

Scheme 67

1. Connect the M-MDS to DLC-2.
2. After the vehicle is identified, select the following items from the initial screen of the M-MDS. When using the IDS (notebook PC) Select the "Module Programming". When using the PDS (pocket PC) Select "Programming". Select "Module Programming".
3. Then, select the "Programmable Module Installation", "PCM" from the screen menu. NOTE: If the PCM is replaced with a new one, the PCM stores DTC P0602, illuminates the MIL even though no malfunction is detected. When the configuration is completed, DTC P0602 is cleared.
4. Retrieve DTC's using the M-MDS, then verify that DTC are present. If a DTC is present, perform the applicable DTC inspection.

Open circuit

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. PSP switch terminal and PCM terminal 2T

Short circuit

1. If there is no continuity, there is a short circuit. Repair or replace the wiring harness. PSP switch terminal and body ground

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. Variable swirl shutter valve switch terminal A and PCM terminal 2AE Variable swirl shutter valve switch terminal B and body ground.

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Variable swirl shutter valve switch terminal A and power supply Variable swirl shutter valve switch terminal A and body ground Variable swirl shutter valve switch terminal B and power supply

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. ECT sensor terminal A and PCM terminal 2AH ECT sensor terminal B and PCM terminal 2AY

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. ECT sensor terminal A and power supply ECT sensor terminal A and body ground ECT sensor terminal B and power supply

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. MAF/IAT sensor terminal A and main relay terminal E MAF/IAT sensor terminal B and PCM terminal 1P MAF/IAT sensor terminal C and PCM terminal 1AK

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. MAF/IAT sensor terminal A and body ground MAF/IAT sensor terminal B and power supply MAF/IAT sensor terminal C and power supply MAF/IAT sensor terminal C and body ground

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. MAF/IAT sensor terminal D and PCM terminal 1M MAF/IAT sensor terminal E and PCM terminal 1AR

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. MAF/IAT sensor terminal E and power supply MAF/IAT sensor terminal D and power supply MAF/IAT sensor terminal D and body ground

Scheme 68

1. Disconnect the negative battery cable.
2. Remove the charge air cooler duct. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION[L3 WITH TC]»(ref-268965-S28635226732007102700000) ).
3. Remove the oil level gauge pipe. (See «OIL PAN REMOVAL/INSTALLATION[L3 WITH TC]»(ref-268963-S23117871082007102700000) ).
4. Disconnect the MAP/boost air temperature sensor connector.
5. Remove MAP/boost air temperature sensor from the intake manifold.
6. Install in the reverse order of removal. Tightening torque 5.0-7.0 N.m {51-71 kgf.cm, 45-61 in.lbf}

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. MAP/boost air temperature sensor terminal A and PCM terminal 2AV MAP/boost air temperature sensor terminal C and PCM terminal 2AU MAP/boost air temperature sensor terminal D and PCM terminal 2AG

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. MAP/boost air temperature sensor terminal A and power supply. MAP/boost air temperature sensor terminal C and body ground. MAP/boost air temperature sensor terminal D and power supply. MAP/boost air temperature sensor terminal D and body ground

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. MAP/boost air temperature sensor terminal A and PCM terminal 2AV MAP/boost air temperature sensor terminal B and PCM terminal 2N MAP/boost air temperature sensor terminal C and PCM terminal 2AU

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. MAP/boost air temperature sensor terminal A and power supply MAP/boost air temperature sensor terminal B and power supply MAP/boost air temperature sensor terminal B and body ground MAP/boost air temperature sensor terminal C and body ground

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. Throttle body terminal A and PCM terminal 2AK Throttle body terminal B and PCM terminal 2AO Throttle body terminal C and PCM terminal 2AL Throttle body terminal D and PCM terminal 2AP

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Throttle body terminal A and power supply Throttle body terminal A and body ground Throttle body terminal B and body ground Throttle body terminal C and power supply Throttle body terminal C and body ground Throttle body terminal D and power supply

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. APP sensor terminal A and PCM terminal 1AJ APP sensor terminal B and PCM terminal 1AV APP sensor terminal C and PCM terminal 1AC APP sensor terminal D and PCM terminal 1Q APP sensor terminal E and PCM terminal 1U APP sensor terminal F and PCM terminal 1Y

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. APP sensor terminal A and body ground APP sensor terminal B and power supply APP sensor terminal C and power supply APP sensor terminal C and body ground APP sensor terminal D and body ground APP sensor terminal E and power supply APP sensor terminal F and power supply APP sensor terminal F and body ground

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. Fuel pressure sensor terminal A and PCM terminal 2P Fuel pressure sensor terminal B and PCM terminal 2R Fuel pressure sensor terminal C and PCM terminal 2I

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Fuel pressure sensor terminal A and power supply. Fuel pressure sensor terminal B and power supply. Fuel pressure sensor terminal B and body ground. Fuel pressure sensor terminal C and body ground

1. If there is no continuity in the following wiring harnesses, there is an open circuit. Repair or replace the wiring harness. Front HO2S terminal 1A and PCM terminal 2AD Front HO2S terminal 1B and PCM terminal 2AC Front HO2S terminal 1C and PCM terminal 2Z Front HO2S terminal 2A and PCM terminal 2M Front HO2S terminal 2B and main relay terminal E Front HO2S terminal 2C and PCM terminal 2Y Front HO2S terminal 2D and PCM terminal 2C

1. If there is continuity in the following wiring harnesses, there is a short circuit. Repair or replace the wiring harness. Front HO2S terminal 1A and body ground Front HO2S terminal 1A and power supply Front HO2S terminal 1B and body ground Front HO2S terminal 1B and power supply Front HO2S terminal 1C and body ground Front HO2S terminal 1C and power supply Front HO2S terminal 2A and power supply Front HO2S terminal 2B and body ground Front HO2S terminal 2C and body ground Front HO2S terminal 2C and power supply Front HO2S terminal 2D and body ground Front HO2S terminal 2D and power supply

Scheme 69

1. Warm up the engine to normal operating temperature.
2. Using the M-MDS, monitor the following: Vehicle speed (PID: VSS) Engine speed (PID: RPM) Rear HO2S voltage (PID: O2S12)
3. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more .
4. Verify that the rear HO2S outputs a voltage of 0.6 V or more, one time or more, then verify that the rear HO2S voltage (PID: O2S12) is 0.3 V or less while decelerating as shown in the figure. If not within the specification, inspect the HO2S for an open or short circuit. (See «REAR HO2S CIRCUIT OPEN/SHORT INSPECTION (SENSOR»(ref-268973-S30312418752007102700000) ).) Then if there is no malfunction in the wiring harness, replace the rear HO2S.

Scheme 70

1. Disconnect the PCM connector.
2. Disconnect the rear HO2S connector.
3. Inspect the following wiring harnesses for an open or short circuit. (Continuity inspection)

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. Rear HO2S terminal A and PCM terminal 2Q Rear HO2S terminal B and PCM terminal 1BC

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Rear HO2S terminal A and body ground Rear HO2S terminal A and power supply Rear HO2S terminal B and power supply

Scheme 71

1. Disconnect the rear HO2S connector.
2. Measure the rear HO2S resistance between terminals C and D. If not within the specification, replace the HO2S. Rear HO2S heater resistance

Scheme 72

1. Disconnect the PCM connector.
2. Disconnect the rear HO2S connector.
3. Inspect the following wiring harnesses for an open or short circuit. (Continuity check)

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. Rear HO2S terminal C and ignition switch Rear HO2S terminal D and PCM terminal 2D

1. If there is no continuity, there is a short circuit. Repair or replace the wiring harness. Rear Rear HO2S terminal A and body ground Rear HO2S terminal B and power supply Rear HO2S terminal B and body ground

1. If there is no continuity, the circuit is open. Repair or replace the wiring harness. CKP sensor terminal A and PCM terminal 2P CKP sensor terminal B and PCM terminal 2W CKP sensor terminal C and main relay terminal E

1. If there is continuity, the circuit is shorted. Repair or replace the wiring harness. CKP sensor terminal A and power supply CKP sensor terminal B and power supply CKP sensor terminal B and body ground CKP sensor terminal C and body ground

1. If there is no continuity, the circuit is open. Repair or replace the wiring harness. CMP sensor terminal A and main relay terminal E CMP sensor terminal B and PCM terminal 2P CMP sensor terminal C and PCM terminal 2S

1. If there is continuity, the circuit is shorted. Repair or replace the wiring harness. CMP sensor terminal A and body ground CMP sensor terminal B and power supply CMP sensor terminal C and body ground CMP sensor terminal C and power supply

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. KS terminal A and PCM terminal 2U KS terminal B and PCM terminal 2V

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. KS terminal A and power supply KS terminal A and body ground KS terminal B and power supply KS terminal B and body ground