2002 MAZDA 6 relay

F2–216
TROUBLESHOOTING
NO.20 FUEL ODOR (IN ENGINE COMPARTMENT)A6E408018881222
Diagnostic Procedure
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20 FUEL ODOR (IN ENGINE COMPARTMENT)
DESCRIPTION•Fuel smell or visible leakage.
POSSIBLE
CAUSE•Excessive fuel pressure
•Suction control valve malfunction (built-in supply pump)
•Fuel pressure limiter malfunction (built-in common rail)
•Fuel pressure sensor or related circuit malfunction
•Fuel leakage
Warning
The following troubleshooting flow chart contains the fuel system diagnosis and repair
procedures. Read the following warnings before performing the fuel system services:
•Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep
sparks and flames away from fuel.
•Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injury or death
and damage. Fuel can also irritate skin and eyes. To prevent this, always complete “BEFORE
REPAIR PROCEDURE” and “AFTER REPAIR PROCEDURE” described in this manual.
STEP INSPECTION RESULTS ACTION
1 Visually inspect fuel leakage at fuel injector and
fuel line.
Is there any fuel leakage?Yes Service as necessary.
No Go to next step.
2 Visually inspect for damaged or cracked fuel
filter.
Is fuel filter okay?Yes Go to next step.
No Replace fuel filter.
3 Inspect fuel pressure sensor.
(See F2–79 FUEL PRESSURE SENSOR
INSPECTION)
Is fuel pressure okay?Yes Go to next step.
No Repair or replace as necessary.
4 Inspect suction control valve.
(See F2–54 SUCTION CONTROL VALVE
INSPECTION)
Is suction control valve okay?Yes Go to next step.
No Repair supply pump.
(See F2–54 SUPPLY PUMP INSPECTION)
5 Perform self-test function using WDS or
equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
NoNo DTC is displayed:
Remove and inspect common rail.
6 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. (See F2–64 PCM REMOVAL/INSTALLATION)

F2–218
TROUBLESHOOTING
6 Perform self-test function using WDS or
equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
NoNo DTC is displayed:
Go to appropriate DTC test.
7 Access ECT PID.
Inspect ECT PID while warming up engine.
Is PID value correct?Yes Go to next step.
No Inspect ECT sensor and related wiring harnesses.
8 Access IAT PID.
Inspect IAT PID while running engine.
Is PID value correct?Yes Go to next step.
No Inspect IAT sensor and related wiring harnesses.
9 Visually inspect CKP sensor and teeth of pulse
wheel.
Are CKP sensor and teeth of pulse wheel okay?Yes Go to next step.
No Replace malfunctioning parts.
10 Measure gap between CKP sensor and teeth of
pulse wheel.
Specification
1.5—2.5 mm {0.059—0.098 in}
Is gap within specification?Yes Go to next step.
No Adjust CKP sensor position.
11 Visually inspect CMP sensor and teeth of pulse
wheel.
Are CMP sensor and teeth of pulse wheel okay?Yes Inspect following PIDs:
(See F2–65 PCM INSPECTION)
•ECT
•IAT
•MAF
•MAP
•RPM
If PID value is not as specified, repair or replace
malfunctioning parts.
If PID value is okay, go to next step.
No Replace malfunctioning parts.
12 Perform EGR system inspection.
Is EGR system okay?Yes Go to next step.
No Repair or replace malfunctioning part according to
EGR system operation results.
13 Remove parts necessary to inspect
turbocharger.
Note
•Do not remove turbocharger.
Inspect if turbocharger compressor wheel is
bent, damaged, or interfering with housing on
vehicle.
Is there any problem?Yes Replace turbocharger.
No Go to next step. STEP INSPECTION RESULTS ACTION

TROUBLESHOOTING
F2–221
F2
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3 Connect WDS or equivalent to DLC-2.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
NoNo DTC is displayed:
Go to next step.
4 Inspect adjustment of accelerator position
sensor and idle switch.
(See F2–72 ACCELERATOR POSITION
SENSOR INSPECTION)
(See F2–70 IDLE SWITCH INSPECTION)
Are accelerator position sensor and idle switch
adjusted correctly?Yes Go to next step.
No Adjust accelerator position sensor and idle switch
correctly.
(See F2–73 ACCELERATOR POSITION SENSOR
ADJUSTMENT)
(See F2–71 IDLE SWITCH ADJUSTMENT)
5 Inspect adjustment of neutral switch.
(See F2–69 NEUTRAL SWITCH INSPECTION)
Is neutral switch adjusted correctly?Yes Go to next step.
No Adjust neutral switch correctly.
6 Visually inspect CMP sensor and teeth of pulse
wheel.
Are CMP sensor and teeth of pulse wheel okay?Yes Inspect following PIDs:
(See F2–65 PCM INSPECTION)
•ECT
•IAT
•MAF
•RPM
If PID value is not as specified, repair or replace
malfunctioning parts.
If PID value is okay, go to next step.
No Replace malfunctioning parts.
7 Inspect fuel injector.
(See F2–56 FUEL INJECTOR INSPECTION)
Is fuel injector okay?Yes Inspect following systems:
•Wheels
•Transaxle and mounts
•Driveline
•Suspension
Service as necessary.
No Repair or replace as necessary.
8 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. (See F2–64 PCM REMOVAL/INSTALLATION) STEP INSPECTION RESULTS ACTION

F2–222
TROUBLESHOOTING
NO.23 A/C DOES NOT WORK SUFFICIENTLYA6E408018881225
Diagnostic Procedure
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23 A/C DOES NOT WORK SUFFICIENTLY
DESCRIPTION•A/C compressor magnetic clutch does not engage when A/C switch is turned on.
POSSIBLE
CAUSE•Improper refrigerant charge amount
•Open A/C switch magnetic clutch
•Open circuit between A/C relay and A/C magnetic clutch
•Poor GND of A/C magnetic clutch
•Improper A/C magnetic clutch clearance
•Refrigerant pressure switch is stuck open
•A/C relay is stuck open
•Improper A/C cut-off control
•Open circuit between A/C switch and PCM through both refrigerant pressure switch and A/C amplifier
STEP INSPECTION RESULTS ACTION
1 Perform self-test function using WDS or
equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
YesNo DTC is displayed:
Go to appropriate DTC test.
2 Disconnect A/C compressor connector.
Start engine and turn A/C switch to ON.
Is there correct voltage at terminal of A/C
compressor magnetic clutch connector?
Specification
More than 10.5 VYes Inspect for GND condition of magnetic clutch on A/C
compressor.
If GND condition is okay, inspect magnetic clutch coil
for open circuit.
No Go to next step.
3 Disconnect refrigerant pressure switch
connector.
Connect jumper wire between terminals of
refrigerant pressure switch connector.
Turn engine switch to ON.
Turn A/C switch on and set blower fan at any
speed.
Measure PCM terminal 84 voltage.
Is voltage below 1.0 V?Yes Inspect refrigerant pressure switch operation.
If switch is okay, go to next step.
No Inspect for following:
•A/C switch is stuck open
•Open circuit between refrigerant pressure switch
and PCM terminal 84
•Open circuit of blower motor fan switch and
resistor (if blower motor does not operate)
•Evaporator temperature sensor and A/C amplifier
4 Inspect A/C cut-off operation.
Does A/C cut-off work properly?Yes Go to next step.
No Repair or replace malfunctioning part according to A/C
cut-off system inspection results.
5 Remove jumper wire from switch connector.
Reconnect connector to refrigerant pressure
switch.
Start engine and turn A/C switch on.
Does fan operate?Yes Inspect for stuck open A/C relay.
Replace if necessary.
No Inspect following and repair or replace as necessary:
•Refrigerant charging amount
•Seized A/C compressor
6 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. (See F2–64 PCM REMOVAL/INSTALLATION)

TROUBLESHOOTING
F2–223
F2
NO.24 A/C ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLYA6E408018881226
Diagnostic Procedure
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24 A/C ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY
DESCRIPTION•A/C compressor magnetic clutch does not disengage.
POSSIBLE
CAUSE•A/C compressor magnetic clutch stuck engagement
•A/C relay is stuck closed
•Improper A/C compressor magnetic clutch clearance
•Short to GND circuit between A/C switch and PCM
•Short to GND circuit between A/C relay and PCM
•A/C relay to magnetic clutch circuit shorts to battery power
STEP INSPECTION RESULTS ACTION
1 Perform self-test function using WDS or
equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
NoNo DTC is displayed:
Go to appropriate DTC test.
2 Start engine and run it at idle.
Turn A/C switch on.
Remove A/C relay.
Does A/C magnetic clutch disengage?Yes Inspect for following:
•A/C relay is stuck closed
•Short to GND circuit between A/C relay and PCM
terminal 73
If both items are okay, go to next step.
No Inspect if circuit between A/C relay and magnetic
clutch shorts to battery power circuit.
If circuit is okay, inspect magnetic clutch stuck
engagement or clearance.
3 Start engine and turn A/C switch on.
Measure PCM terminal 84 voltage while
disconnecting refrigerant pressure switch
connector.
Note
•PCM terminal 84 voltage should read B+
when disconnecting connector. If PCM
terminal 84 voltage reading remains
below 1.0 V, short to GND circuit may be
present.
Is voltage B+?Yes Inspect for short to GND circuit between refrigerant
pressure switch and PCM terminal 84.
No Go to next step.
4 Reconnect refrigerant pressure switch
connector.Measure PCM terminal 84 voltage
while turning off A/C switch.
Note
•PCM terminal 84 voltage should read B+
when turning A/C switch off. If PCM
terminal 84 voltage reading remains
below 1.0 V, short to GND circuit maybe
present.
Does voltage remain B+?Yes Inspect for following:
•Short to GND circuit between A/C switch and A/C
amplifier.
•Short to GND circuit between A/C amplifier and
refrigerant pressure switch.
No Inspect for stuck closed A/C switch.
5 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. (See F2–64 PCM REMOVAL/INSTALLATION)

F2–224
TROUBLESHOOTING
NO.25 A/C DOES NOT CUT OFF UNDER WIDE OPEN THROTTLE CONDITIONSA6E408018881227
Diagnostic Procedure
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25 A/C DOES NOT CUT OFF UNDER WIDE OPEN THROTTLE CONDITIONS
DESCRIPTION•A/C compressor magnetic clutch does not disengage under wide open throttle.
POSSIBLE
CAUSE•Accelerator position sensor malfunction
•Accelerator position sensor misadjustment
•Loosely installed accelerator position sensor
STEP INSPECTION RESULTS ACTION
1 Does A/C compressor disengage when A/C
switch is turned off?Yes Go to next step.
No Go to symptom troubleshooting “NO.24 A/C ALWAYS
ON OR A/C COMPRESSOR RUNS
CONTINUOUSLY”.
2 Perform self-test function using WDS or
equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open.
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
NoNo DTC is displayed:
Inspect adjustment of accelerator position sensor.
If accelerator position sensor adjustment is not
correct, adjust accelerator position sensor.
3 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. (See F2–64 PCM REMOVAL/INSTALLATION)

TROUBLESHOOTING
F2–225
F2
NO.26 CONSTANT VOLTAGEA6E408018881228
Diagnostic Procedure
26 CONSTANT VOLTAGE
DESCRIPTION•Incorrect constant voltage.
POSSIBLE
CAUSE•Constant voltage circuit malfunction
•Accelerator positions sensor or related circuit malfunction
•Fuel pressure sensor or related circuit malfunction
•Boost sensor or related circuit malfunction
•ECT sensor GND circuit malfunction
•MAF/IAT sensor GND circuit malfunction
•IAT sensor No.2 GND circuit malfunction
•Fuel temperature sensor GND circuit malfunction
Note
•Accelerator position sensor, fuel pressure sensor and boost sensor use constant voltage.
STEP INSPECTION RESULTS ACTION
1 Disconnect appropriate sensor connectors
(accelerator position sensor, boost sensor and
fuel pressure sensor) where constant voltage
circuits inspection failed.
Turn engine switch to ON position.
Measure voltage between following appropriate
sensor connector terminals:
•Constant voltage terminal and GND terminal.
Is constant voltage above 6.0 V?Yes Repair constant voltage circuit short to power in
harness.
No Go to next step.
2 Is voltage across battery terminals above 10.5
V?Yes Go to next step.
No Inspect charging system.
3 Turn engine switch to OFF.
Leave appropriate sensor connectors
disconnected where constant voltage inspection
failed.
Measure voltage between positive terminal and
GND circuit at appropriate sensor vehicle
harness connector.
Is voltage above 10.5 V and within 1.0 V of
battery voltage?Yes Go to next step.
No Go to Step 8.
4Note
•Purpose of this step is to determine if
WDS or equivalent is communicating with
PCM.
Turn engine switch to ON.
Attempt to access ECT PID.
Can ECT PID be accessed?Yes Go to Step 7.
No Go to next step.
5 Turn engine switch to OFF.
Disconnect accelerator position sensor and
PCM connectors.
Turn engine switch to ON.
Measure voltage between PCM connector
terminals 104 and 53/79.
Is voltage greater than 10.5 V?Yes Go to next step.
No Repair open circuit between PCM terminal 53/79 and
PCM control relay.
6 Leave accelerator position sensor and PCM
connectors disconnected.
Measure resistance between PCM connector
terminals 104 and 90.
Is resistance greater than 10,000 ohms?Yes Inspect sensor connector for constant voltage again.
No Repair constant voltage circuit short to GND.
7 Turn engine switch to OFF.
Leave accelerator position sensor
disconnected.Disconnect PCM connector.
Measure resistance between PCM connector 90
and constant voltage circuit at appropriate
sensor connector.
Is resistance less than 5.0 ohms?Yes Inspect sensor connector for constant voltage again.
No Repair open constant voltage circuit.

F2–228
TROUBLESHOOTING
Inspection Method for Sensors
1. Connect the WDS or equivalent to the DLC-2.
2. Turn the engine switch to ON (Engine OFF).
Note
•If the engine starts and runs, perform the following steps at idle.
3. Access PIDs for the switch you are inspecting.
4. Vibrate the sensor slightly with your finger.
•If the PID value is unstable or malfunction occurs, check for poor connection and/or poorly mounted
sensor.
Inspection Method for Actuators or Relays
1. Connect the WDS or equivalent to the DLC-2.
2. Turn the engine switch to ON (Engine OFF).
Note
•If the engine starts and runs, perform the following steps at idle.
3. Prepare the Output State Control for actuators or relays that you are inspecting.
4. Vibrate the actuator or relay with your finger for 3
seconds after Output State Control is activated.
•If a variable click sound is heard, check for
poor connection and/or poorly mounted
actuator or relay.
Note
•Vibrating relays too strongly may result in
open relays.
Water Sprinkling Method
Caution
•Indirectly change the temperature and humidity by spraying water onto the front of the radiator.
•If a vehicle is subject to water leakage, the leakage may damage the control module. When testing
a vehicle with a water leakage problem, special caution must be used.
If malfunction occurs only during high humidity or rainy/snowy weather, perform the following steps.
1. Connect the WDS or equivalent to the DLC-2 if you are inspecting sensors or switches.
2. Turn the engine switch to ON (Engine OFF).
Note
•If the engine starts and runs, perform the following steps at idle.
3. Access PIDs for sensor or switch if you are inspecting sensors or switches.
4. If you are inspecting a switch, turn it on manually.
5. Spray water onto the vehicle or run it through a
car wash.
•If the PID value is unstable or malfunction
occurs, repair or replace part as necessary.
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A6E40802003
A6E40802004