Ford Falcon. Manual — part 311

412-03-17 Air

Conditioning 412-03-17

DIAGNOSIS AND TESTING (Continued)

Symptom

Possible Cause

Possible Root

Confirmation Test

Possible Fix

Area

Cause

A/C component

Conduct A/C noise

Isolate noise source

resonance/rattling

test and detect

noise source

Comp. discharge

Conduct A/C noise

Isolate noise

pulsation noise

test

condition

transfer to body
Excessive

Conduct A/C

Recharge A/C

compressor noise

Performance test to system to

due to overcharged

judge overcharged

specifications

system
Refrigerant flow

Conduct A/C

Recharge A/C

hiss/gurgle due to

Performance test to system to

overcharged system judge overcharged

specification,

Refrigerant flow

Conduct A/C noise

Isolate/replace A/C

hiss/gurgle due to

test and detect

liquid line

A/C liquid line noise noise source

transmission
Refrigerant flow

Conduct A/C noise

Replace orifice tube

hiss/gurgle due to

test

and/or liquid line

faulty orifice tube

Control component

Intermittent A/C

Intermittent power to Compressor wiring

Repair circuit

fault

operation

clutch

fault, refer to

Pinpoint test A

Pressure transducer Open-circuit

Go to Pinpoint test

Repair fault, replace

fault

C

part

Short circuit

Go to Pinpoint test

Repair fault, replace

C

part

Calibration fault

Go to Pinpoint test

Replace sensor

C

Cabin temperature

Open-circuit

Go to section

Repair fault, replace

sensor fault

412-04

part

Short circuit

Go to section

Repair fault, replace

412-04

part

Calibration fault

Go to section

Replace sensor

412-04

Ambient

Open-circuit

Go to section

Repair fault, replace

temperature sensor

412-04

part

fault

Short circuit

Go to section

Repair fault, replace

412-04

part

Calibration fault

Go to section

Replace sensor

412-04

Sun Load sensor

Open-circuit

Go to section

Repair fault, replace

fault

417-01

part

Short circuit

Go to section

Repair fault, replace

417-01

part

Calibration fault

Go to section

Replace sensor

417-01

Evaporator

Open Circuit

Go to Pinpoint test

Repair fault, replace

Thermistor fault

G

part

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412-03-18 Air

Conditioning 412-03-18

DIAGNOSIS AND TESTING (Continued)

Symptom

Possible Cause

Possible Root

Confirmation Test

Possible Fix

Area

Cause

Calibration fault

Go to Pinpoint test

Replace sensor

G

ICC display screen

Not working,

Refer to 413-08

Refer 413-08

or button fault

Incorrect operation

For additional information, refer to Section 412-00.

3. Insert a thermometer (or temperature measuring

device) into one of the Centre Face Level

Air Conditioning System Performance

Registers. Monitor the Register air outlet

Test

temperature and record only when it is stable. (ie:

When the temperature has stopped falling). Allow

NOTE: This test is used to ascertain the maximum

a minimum of 5 minutes for the Register air

cooling capability of the air conditioning system.

temperature to stabilise before taking readings.

4. Monitor the pressure gauge readings and record

Vehicle preparation:

stabilised pressures.

NOTE: Check the following items before carrying out

NOTE: Pressure modulations even when the

the test - adjust as necessary.

system has stabilised is normal.

1. No heat pickup when the A/C controls are in the

5. If the system cycles, record the maximum and

full cold position.

minimum vent temperatures, maximum discharge

2. The engine cooling fans for correct operation and

pressure, minimum suction pressure and

providing adequate condender airflow.

approximate clutch on and off time in seconds.

3. Condenser and Radiator core fin condition

NOTE: Cycling should only occur at lower

(obstruction by insect, grass, screens etc.).

ambient temperatures. (Refer to Recommended

Compressor Cycle Times overpage.)

4. Full Recirculation air mode is achieved.
5. Compressor drive belt tension.

6. Record the Ambient air temperature of the day

away from direct sunload using the air

6. Face level air outlet mode achieved.

temperature measuring device.

7. Temperature door is achieving full cold position.

7. For the air register vent temperatures, if the

8. Correct operation of Automatic Climate Control

system was cycling, calculate the average of the

system (Perform diagnosis self-test).

maximum and minimum temperatures. Use the

9. Engine coolant level in radiator supply tank.

AVERAGE register temperature for comparison

against the normal values on the graph. If the

Test Conditions:

system was not cycling, compare the measured

1. Engine Idling at operating temperature with the

vent temperature against the normal values on

transmission in Park with the handbrake applied.

the graph.

2. Vehicle doors closed with all windows fully

8. Next, compare these temperature and pressure

opened and bonnet raised.

readings with Normal values between the upper

and lower limits shown in the graphs below. Using

3. An R134 Manifold Gauge set connected to the

this information and the Diagnostics table, the

high and low side service port connections.

likely cause of capacity loss can be diagnosed.

4. The vehicle positioned in the shade at least 1.5

For more information on A/C system diagnosis,

metres from any wall.

refer to the A/C fault symptom chart in this

5. Air conditioning operating on recirc, face, full cold,

section.

(max.) high blower fan for 5 minutes until A/C

system temperatures stable.

CAUTION: Never top-up with R134a. If low

R134a charge is suspected remove the

Test Procedure:

remaining charge and re-fill with the

recommended R134a quantity.

1. Run with the engine idling and A/C set as per test

conditions for 5 minutes until the A/C system

temperatures are stable.
NOTE: To achieve these settings on automatic

climate control vehicles, select manual over-rides.

2. Confirm that the Compressor is engaged.

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412-03-19 Air

Conditioning 412-03-19

DIAGNOSIS AND TESTING (Continued)

Normal centre register Average Air Temperature

NOTE: RECOMMENDED COMPRESSOR CYCLE

TIMES:
In ambient temperatures below about 25

°C, the

A/C compressor cycle time will vary.
For reference:

The compressor should cycle ON for 5

MINIMUM to 30 seconds.
The compressor should cycle OFF for 2 — 12

MAXIMUM seconds.

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412-03-20 Air

Conditioning 412-03-20

DIAGNOSIS AND TESTING (Continued)

Normal High side Pressure

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