Mazda Protege 5. Manual - part 272

SYMPTOM TROUBLESHOOTING 

07–03–7

07–03

2

INSPECT REFRIGERANT SYSTEM 
PERFORMANCE

•

Perform refrigerant system performance test.
(See 07–10–2 REFRIGERANT SYSTEM 
PERFORMANCE TEST)

•

Is operation normal?

Yes

Operation is normal. (Recheck malfunction symptoms.)

No

Go to next step.

3

CHECK TO SEE WHETHER MALFUNCTION 
IS IN BLOWER UNIT INTAKE AND 
CONDENSER OR ELSEWHERE

•

Are refrigerant high-pressure and low-
pressure values both high?

Yes

Go to next step.

No

Go to Step 6.

4

INSPECT BLOWER UNIT INTAKE

•

Is blower unit intake clogged?

Yes

Remove obstruction, then go to Step 20. (If air does not 
reach evaporator within cooling unit, heat exchange does 
not occur and refrigerant pressure becomes high.
Therefore, removal of obstruction is necessary.)

No

Go to next step.

5

INSPECT CONDENSER

•

Inspect condenser.
(See 07–11–13 CONDENSER 
INSPECTION)

•

Is it okay?

Yes

Adjust refrigerant to specified amount, then go to Step 20. 
(Excessive amount of refrigerant.)

No

Replace condenser, or repair and clean condenser fins, 
then go to Step 20.

6

CHECK TO SEE WHETHER MALFUNCTION 
IS IN EXPANSION VALVE, RECEIVER/DRIER 
AND REFRIGERANT LINES OR ELSEWHERE

•

Are refrigerant high-pressure and low-
pressure values low?

Yes

Go to next step.

No

Go to Step 14.

7

CHECK TO SEE WHETHER MALFUNCTION 
IS IN EXPANSION VALVE AND RECEIVER/
DRIER OR ELSEWHERE

•

Immediately after A/C compressor operates, 
does refrigerant high-pressure value 
momentarily rise to correct value, then fall 
and stay below it? (Is there negative 
pressure on low-pressure side?)

Yes

Go to next step.

No

Go to Step 10.

8

CHECK TO SEE WHETHER MALFUNCTION 
IS IN EXPANSION VALVE OR RECEIVER/
DRIER

•

Turn A/C switch off and let air conditioner 
stop for 10 minutes.

•

Start engine.

•

Turn both A/C switch and fan switch on.

•

Does malfunction occur after A/C 
compressor turns on?

Yes

Go to next step.

No

Replace receiver/drier and vacuum refrigerant line more 
than 30 minutes by vacuum pump, add refrigerant to 
specified level, then go to Step 20. (Since water has 
intermixed in receiver/drier and it is saturated, replacement 
is necessary.)

9

VERIFY THAT EXPANSION VALVE HEAT-
SENSING TUBE WITHIN COOLING UNIT IS 
POSITIONED SECURELY AND CORRECTLY

•

Is expansion valve heat-sensing tube within 
cooling unit securely installed in proper 
position?

Yes

Replace expansion valve, then go to Step 20. (Since valve 
closes too much, replacement is necessary.)

No

Install heat-sensing tube securely in proper position, then go 
to Step 20.

10

INSPECT REFRIGERANT LINES

•

Inspect refrigerant lines.
— Is piping free of damage and cracks?
— Are piping connections free of oil grime? 

(Visual inspection)

— Are piping connections free of gas 

leakage?

— Are piping installation points on 

condenser free of gas leakage?

— Are piping installation points on receiver/

drier free of gas leakage?

— Are piping installation points on A/C 

compressor free of gas leakage?

— Are piping installation points on cooling 

unit free of gas leakage?

— Perform gas leak inspection using gas 

leak tester.

•

Are above items okay?

Yes

Go to next step.

No

If piping or A/C component(s) are damaged or cracked, 
replace them.
Then go to Step 20.
If there is no damage, go to Step 13.

STEP

INSPECTION

ACTION

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SYMPTOM TROUBLESHOOTING 

07–03–8

11

INSPECT EVAPORATOR PIPING 
CONNECTIONS IN COOLING UNIT FOR GAS 
LEAKAGE

•

Are piping connections for evaporator in 
cooling unit free of gas leakage?

Yes

If the vane makes a noise, add 10 ml {10 cc, 0.34 fl oz} of 
compressor oil to the A/C compressor. Verify that the noise 
is no longer heard.
Adjust refrigerant to specified amount, then go to Step 20.

No

If piping is damaged or cracked, replace it.
Then go to Step 20.
If there is no damage, go to next step.

12

INSPECT EVAPORATOR PIPING 
CONNECTIONS IN COOLING UNIT FOR 
LOOSE

•

Are piping connections for evaporator in 
cooling unit loose?

Yes

Tighten connections with specified torque, adjust both 
compressor oil and refrigerant to specified amount, then go 
to Step 20.

No

If the vane makes a noise, add 10 ml {10 cc, 0.34 fl oz} of 
compressor oil to the A/C compressor. Verify that the noise 
is no longer heard.
Replace O-ring on piping, adjust refrigerant to specified 
amount, then go to Step 20.

13

INSPECT PIPING CONNECTIONS FOR 
LOOSE

•

Are piping connections loose?

Yes

Tighten connections with specified torque, adjust both 
compressor oil and refrigerant to specified amount, then go 
to Step 20.

No

If the vane makes a noise, add 10 ml {10 cc, 0.34 fl oz} of 
compressor oil to the A/C compressor. Verify that the noise 
is no longer heard.
Replace O-ring on piping, adjust refrigerant to specified 
amount, then go to Step 20.

14

CHECK TO SEE WHETHER MALFUNCTION 
IS IN EXPANSION VALVE, AIR MIX 
ACTUATOR AND COMPRESSOR OIL OR 
ELSEWHERE

•

Does refrigerant high-pressure value hardly 
increase?

Yes

Go to next step. (Pressure hardly increases.)

No

Go to Step 17.

15

CHECK TO SEE WHETHER MALFUNCTION 
IS IN COMPRESSOR OIL AMOUNT AND A/C 
COMPRESSOR OR ELSEWHERE

•

When engine is racing, does high-pressure 
value increase?

Yes

Return to Step 3.

No

Go to next step.

16

CHECK TO SEE WHETHER MALFUNCTION 
IS IN COMPRESSOR OIL AMOUNT OR A/C 
COMPRESSOR

•

After compressor oil is replenished each 10 
ml {10 cc, 0.34 fl oz}, does high-pressure 
value increase?

Yes

Troubleshooting completed. (Explain to customer that cause 
was insufficient compressor oil.)

No

Replace A/C compressor, then go to Step 20. (Cause is 
defective A/C compressor.)

17

CHECK TO SEE WHETHER MALFUNCTION 
IS IN EXPANSION VALVE OR ELSEWHERE

•

Is only refrigerant low-pressure value high?

Yes

Go to Step 19.

No

Go to next step.

18

VERIFY THAT AIR MIX IS INSTALLED 
SECURELY AND PROPERLY

•

Are heater unit air mix links, air mix cranks, 
and air mix rods securely and properly 
installed?

Yes

Set fan switch to 4th position.
Turn A/C switch on.
Set FRESH mode.
Set temperature control to MAX COLD.
Set VENT mode.

(1)Start and run the engine at 1,500 rpm for 10 minutes.
(2)Run the engine at idle for 1 minute.
(3)Within 12 seconds, idle 

→

 4,000 rpm 

→

 idle. Perform 

cycle 5 times.

(4) Run the engine at idle for 30 seconds.
(5)Drain the compressor oil completely from the A/C 

compressor and verify the amount.

•

If there is approximately 90 ml {90 cc, 3.0 fl oz} of 
compressor oil, go to Step 20.

•

If there is more than 90 ml {90 cc, 3.0 fl oz} of 
compressor oil, remove surplus oil and fill A/C 
compressor with 90 ml {90 cc, 3.0 fl oz} of 
compressor oil. Repeat Steps (1) to (5).

(Cause is excessive amount of compressor oil.)

No

Repair or install links, cranks and rods securely in proper 
position, then go to Step 20.

STEP

INSPECTION

ACTION

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SYMPTOM TROUBLESHOOTING 

07–03–9

07–03

End Of Sie

NO.7 NO COOL AIR

A3U070301038W09

•

When performing an asterisked (*) troubleshooting inspection, shake the wiring harness and connectors while 
doing the inspection to discover whether poor contact points are the cause of any intermittent malfunctions. If 
there is a problem, check to make sure connectors, terminals and wiring harness are connected correctly and 
undamaged.

Diagnostic procedure

19

VERIFY THAT EXPANSION VALVE HEAT-
SENSING TUBE WITHIN COOLING UNIT IS 
POSITIONED SECURELY AND CORRECTLY

•

Is expansion valve heat-sensing tube within 
cooling unit securely installed in proper 
position?

Yes

Replace expansion valve, then go to next step. (Since valve 
opens too much, replacement is necessary.)

No

Install heat-sensing tube securely in proper position, then go 
to next step.

20

VERIFY THAT MALFUNCTION SYMPTOM 
OCCURS AFTER REPAIR

•

Does cool air blow out? (Are results of 
refrigerant system performance test okay?)

Yes

Troubleshooting completed.
Explain repairs to customer.

No

Recheck malfunction symptoms, then repeat from Step 1 if 
malfunction recurs.

STEP

INSPECTION

ACTION

7

No cool air.

DESCRIPTION

•

Magnetic clutch does not operate.

POSSIBLE 

CAUSE

•

PCM A/C cut-off control system, coolant system malfunction (Steps 4, 17)

•

A/C amplifier, A/C switch malfunction (Steps 6—10)

•

PCM (A/C signal) system malfunction (Steps 11,12)

•

Refrigerant pressure switch, refrigerant system malfunction (Steps 13, 14)

•

PCM (IG1 signal) system malfunction (Steps 15, 16)

•

A/C compressor system malfunction (Step 18)

•

A/C relay system malfunction (Steps 19—21)

STEP

INSPECTION

ACTION

1

CHECK AIRFLOW

•

Does air blow out?

Yes

Go to next step.

No

Go to Step 1 of troubleshooting indexes No. 1, 2.

2

INSPECT A/C COMPRESSOR OPERATION

•

Start engine.

•

Turn both A/C switch and fan switch on.

•

Does A/C compressor operate?

Yes

Go to Step 1 of troubleshooting index No. 6.

No

Go to next step.

*3

CHECK TO SEE WHETHER MALFUNCTION 
(LACK OF CONTINUITY) IS IN CLIMATE 
CONTROL UNIT OR WIRING HARNESS 
(BETWEEN A/C SWITCH AND FAN SWITCH)

•

Turn both A/C switch and fan switch off.

•

Test voltage at climate control unit terminal D 
(A/C signal).

•

Is voltage approximately 12 V?

Yes

Go to next step.

No

Repair wiring harness between climate control unit and fan 
switch, then go to Step 22.

4

CHECK FOR DTCS IN PCM

•

Check the DTC for the PCM on-board 
diagnostic system.

•

Are any DTCs displayed?
(See 01–03B–4 FOREWORD [FS])
(See 01–03A–4 FOREWORD [ZM])

Yes

Go to appropriate inspection procedure.

No

Go to next step.

*5

CHECK TO SEE WHETHER MALFUNCTION 
IS IN A/C AMPLIFIER SYSTEM OR 
ELSEWHERE

•

Turn ignition switch to LOCK position.

•

Disconnect refrigerant pressure switch 
connector.

•

Turn ignition switch to ON position.

•

Set fan switch to 1st speed.

•

Test voltage at following terminal of 
refrigerant pressure switch connector (on 
wiring harness side).
— Terminal A (A/C signal)

•

Is voltage approximately 12 V when A/C 
switch is off and 0 V when it is on?

Yes

Go to Step 11.

No

Reconnect refrigerant pressure switch connector, then go to 
next step.

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SYMPTOM TROUBLESHOOTING 

07–03–10

*6

CHECK TO SEE WHETHER MALFUNCTION 
IS IN A/C AMPLIFIER (LACK OF CONTINUITY 
OR SHORT TO GROUND) AND WIRING 
HARNESS (LACK OF CONTINUITY OR 
SHORT TO GROUND BETWEEN FUSE 
BLOCK AND A/C AMPLIFIER) OR 
ELSEWHERE

•

Turn ignition switch to LOCK position.

•

Disconnect A/C amplifier connector.

•

Start engine.

•

Turn both A/C switch and fan switch on.

•

When A/C amplifier connector terminals B 
and C (on wiring harness side) are shorted, 
does cool air blow out?

Yes

Go to next step.

No

Go to Step 8.

*7

CHECK TO SEE WHETHER MALFUNCTION 
(LACK OF CONTINUITY OR SHORT TO 
GROUND) IS IN A/C AMPLIFIER OR WIRING 
HARNESS (BETWEEN FUSE BLOCK AND A/
C AMPLIFIER)

•

Turn ignition switch to ON position.

•

Test voltage at A/C amplifier connector 
terminal A (IG2 signal).

•

Is voltage approximately 12 V?

Yes

Inspect A/C amplifier, then go to Step 22.

No

Repair wiring harness between fuse block and A/C 
amplifier, then go to Step 22.

*8

INSPECT WIRING HARNESS BETWEEN 
REFRIGERANT PRESSURE SWITCH AND A/
C AMPLIFIER FOR SHORT TO B+

•

Test voltage at A/C amplifier connector 
terminal B (A/C signal).

•

Is voltage approximately 12 V?

Yes

Repair wiring harness between refrigerant pressure switch 
and A/C amplifier, then go to Step 22.

No

Go to next step.

*9

INSPECT WIRING HARNESS BETWEEN 
REFRIGERANT PRESSURE SWITCH AND A/
C AMPLIFIER FOR CONTINUITY

•

Turn ignition switch to LOCK position.

•

Disconnect refrigerant pressure switch 
connector.

•

Inspect for continuity between A/C amplifier 
connector terminal B (A/C signal) and 
refrigerant pressure switch connector 
terminal A.

•

Is there continuity?

Yes

Go to next step.

No

Repair wiring harness between refrigerant pressure switch 
and A/C amplifier, then go to Step 22.

*10

CHECK TO SEE WHETHER MALFUNCTION 
(SHORT TO B+) IS IN CLIMATE CONTROL 
UNIT OR WIRING HARNESS (BETWEEN 
CLIMATE CONTROL UNIT AND A/C 
AMPLIFIER)

•

Turn ignition switch to ON position.

•

Turn A/C switch on.

•

Turn fan switch off.

•

Test voltage at climate control unit connector 
terminal B (A/C signal).

•

Is voltage approximately 12 V?

Yes

Inspect wiring harness between A/C amplifier and climate 
control unit, then go to Step 22.

No

Inspect climate control unit, then go to Step 22.

*11

CHECK TO SEE WHETHER MALFUNCTION 
IS IN PCM (LACK OF CONTINUITY) AND 
WIRING HARNESS (BETWEEN PCM AND 
REFRIGERANT PRESSURE SWITCH) OR 
ANOTHER AREA

•

Test voltage at refrigerant pressure switch 
connector (on wiring harness side) terminal 
B (A/C signal).

•

Turn ignition switch to ON position.

•

Is voltage approximately 12 V?

Yes

Go to Step 13.

No

Go to next step.

*12

CHECK TO SEE WHETHER MALFUNCTION 
IS IN PCM OR WIRING HARNESS (BETWEEN 
PCM AND REFRIGERANT PRESSURE 
SWITCH FOR CONTINUITY)

•

Test voltage at PCM connector (96-pin) 
terminal (A/C signal terminal).

•

Is voltage approximately 12 V?

Yes

Repair wiring harness between PCM and refrigerant 
pressure switch, then go to Step 22.

No

Inspect PCM, then go to Step 22.

STEP

INSPECTION

ACTION

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