Insufficient air heating in the cabin or windshield
Attention! When heated, the pressure in the cooling system increases. Removing the expansion tank cap when the engine is not cool enough can cause injury.
Step | Operation | Values | Yes | No |
1 |
Make sure the customer's complaint is validated.
Are the customer's complaints validated?
|
-
|
Go to operation 2
|
System OK
|
2 |
Check coolant level.
Is the coolant level correct?
|
-
|
Go to operation 4
|
Go to operation 3
|
3 |
Top up coolant if necessary.
Has the renovation been completed?
|
-
|
System OK
|
Go to operation 4
|
4 |
Check tension and damage to drive belts.
Are the drive belts ok?
|
-
|
Go to operation 6
|
Go to operation 5
|
5 |
Eliminate the identified defects in the drive belts.
Has the renovation been completed?
|
-
|
System OK
|
Go to operation 6
|
6 |
Check coolant hoses for leaks or kinks.
Are the coolant hoses OK?
|
-
|
Jump to operation 8
|
Jump to Operation 7
|
7 |
Troubleshoot coolant hoses.
Has the renovation been completed?
|
-
|
System OK
|
Jump to operation 8
|
8 |
Check expansion tank cap for leaks.
Expansion tank cap OK?
|
-
|
Jump to operation 10
|
Go to operation 9
|
9 |
If necessary, replace the expansion tank cap.
Has the renovation been completed?
|
-
|
System OK
|
Jump to operation 10
|
10 |
Is there strong airflow from the heater outlet?
|
-
|
Go to operation 11
|
Go to operation 26
|
11 |
Check the change in air flow by changing the fan speed.
Does the fan speed increase when switching from minimum to maximum?
|
-
|
Go to operation 12
|
|
12 |
Can you see coolant movement?
|
-
|
Go to operation 14
|
Jump to operation 13
|
13 |
Have the problems been fixed?
|
-
|
System OK
|
Go to operation 14
|
14 |
Does the temperature at the outlet of the heater comply with the minimum values given?
|
Ambient
-18°C (0°F)
-4°C (25°F)
10°C (50°F)
24°C (75°F)
Heater outlet
54°C (129°F)
59°C (138°F)
64°C (147°F)
68°C (154°F)
|
Go to operation 15
|
Jump to operation 16
|
15 |
Have the problems been fixed?
|
-
|
System OK
|
-
|
16 |
Does the damper click?
|
-
|
Go to operation 18
|
Go to operation 17
|
17 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
18 |
Is the heater inlet hose hot and the heater outlet hose warm?
|
-
|
Jump to operation 19
|
Go to operation 22
|
19 |
Check thermostat. See section 1D, "Engine cooling".
Is the thermostat properly installed and sealed?
|
-
|
Jump to operation 20
|
Jump to Operation 21
|
20 |
Replace thermostat. See section 1D, "Engine cooling".
Has the renovation been completed?
|
-
|
System OK
|
-
|
21 |
Install the thermostat.
Has the renovation been completed?
|
-
|
System OK
|
-
|
22 |
Check that the heater hoses are installed correctly.
Are the heater hoses connected backwards?
|
-
|
Jump to operation 23
|
Jump to Operation 24
|
23 |
Install heater hoses correctly.
Has the renovation been completed?
|
-
|
System OK
|
-
|
24 |
Is the heater inlet hose hot and the heater outlet hose warm?
|
-
|
System OK
|
Jump to operation 25
|
25 |
Replace heater heat exchanger.
Has the renovation been completed?
|
-
|
System OK
|
-
|
26 |
Retest the system according to the test procedures "Position of controls/correct results". See "Incorrect air distribution or no mode switching" in this section.
Has the renovation been completed?
|
-
|
System OK
|
Go to operation 27
|
27 |
Check airflow from defroster openings or vents.
Is there strong airflow from the defroster openings or vents?
|
-
|
Jump to operation 28
|
Jump to operation 29
|
28 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
29 |
Set the mode switch to the defrost position.
Is the defroster air flow OK?
|
-
|
Jump to operation 30
|
Jump to Operation 31
|
30 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
31 |
Check the change in air flow at different fan speeds.
Does the fan speed increase when switching from position 1 to position 4?
|
-
|
Go to operation 32
|
|
32 |
Check for obstructions in the system at the fan inlet and on the air filter, if the vehicle has one.
Are obstacles found?
|
-
|
Jump to Operation 33
|
Go to operation 34
|
33 |
Remove obstruction from system at fan inlet or replace clogged filter.
Has the renovation been completed?
|
-
|
System OK
|
-
|
34 |
Does the airflow change?
|
-
|
Go to operation 35
|
Jump to operation 36
|
35 |
Has the renovation been completed?
|
-
|
Jump to operation 1
|
-
|
36 |
Has the renovation been completed?
|
-
|
Jump to operation 1
|
-
|
Electric fan
Step | Operation | Values | Yes | No |
1 |
Make sure the customer's complaint is validated.
Are the customer's complaints validated?
|
-
|
Go to operation 2
|
System OK
|
2 |
Turn on the fan.
Does the fan run at any speed?
|
-
|
Go to operation 14
|
Go to operation 3
|
3 |
Is there tension?
|
11-14 V
|
Go to operation 4
|
Go to operation 5
|
4 |
Replace electric fan.
Has the renovation been completed?
|
-
|
System OK
|
-
|
5 |
Check fuse F18 in the engine fuse box.
Has the fuse blown?
|
-
|
Go to operation 6
|
Jump to Operation 7
|
6 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
7 |
Mass ok?
|
-
|
Go to operation 9
|
Jump to operation 8
|
8 |
Repair the fan ground connection.
Has the renovation been completed?
|
-
|
System OK
|
-
|
9 |
Check the motor connector with a 12 volt test lamp.
Does the control lamp light up?
|
-
|
Jump to operation 10
|
Go to operation 11
|
10 |
Repair an open in the power supply wiring from the resistor pack to the electric fan.
Has the renovation been completed?
|
-
|
System OK
|
-
|
11 |
Using a 12 volt test light, check the power leads at the fan speed switch.
Does the lamp light up?
|
-
|
Go to operation 12
|
Jump to operation 13
|
12 |
Replace fan speed switch.
Has the renovation been completed?
|
-
|
System OK
|
-
|
13 |
Repair open in power wiring from fan speed switch to fuse panel.
Has the renovation been completed?
|
-
|
System OK
|
-
|
14 |
Turn on the fan at speed 4.
Fan not running at speed 4?
|
-
|
Go to operation 15
|
Jump to Operation 21
|
15 |
Check fuse EF2 in the engine fuse box.
Has the fuse blown?
|
-
|
Jump to operation 16
|
Go to operation 17
|
16 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
17 |
Is there tension?
|
-
|
Go to operation 18
|
Jump to operation 19
|
18 |
Replace fan speed switch.
Has the renovation been completed?
|
-
|
System OK
|
-
|
19 |
Has the renovation been completed?
|
-
|
System OK
|
Jump to operation 20
|
20 |
Replace the high fan speed relay.
Has the renovation been completed?
|
-
|
System OK
|
-
|
21 |
Does the test lamp light up on all outputs?
|
-
|
Jump to operation 23
|
Go to operation 22
|
22 |
Replace resistor block.
Has the renovation been completed?
|
-
|
System OK
|
-
|
23 |
Does the test light come on on all three wires?
|
-
|
Jump to operation 25
|
Jump to Operation 24
|
24 |
Replace fan speed switch.
Has the renovation been completed?
|
-
|
System OK
|
-
|
25 |
Repair open in damaged wire.
Has the renovation been completed?
|
-
|
System OK
|
-
|
Incorrect air distribution or no mode switching
This procedure includes checking all functions of the passenger compartment heating system and windows.
1. Warm up the car.
2. Leave the engine running.
3. Perform the checks described in the following table and compare the results.
POSITION OF GOVERNING BODIES
|
CORRECT RESULTS
|
|||||||
Mode switch knob
|
Temp controller
|
FAN SWITCH
|
FAN SPEED
|
Side outlet vent
|
Central outlet vent
|
FLOOR RELEASE
|
HEATED GLASS OUTLET
|
SIDE WINDOW RELEASE
|
Ventilation
|
Cold
|
Off
|
Off
|
No airflow
|
No airflow
|
No airflow
|
No airflow
|
No airflow
|
Ventilation
|
Cold
|
4
|
high
|
Outside air flow
|
Outside air flow
|
No airflow
|
No airflow
|
No airflow
|
Hole
|
from cold to warm
|
4
|
high
|
Minimum airflow from cold to warm
|
No airflow
|
Airflow from cold to warm
|
Minimum airflow from cold to warm
|
Minimum airflow from cold to warm
|
Glass heating (Defroster)
|
from cold to warm
|
4
|
high
|
Minimum airflow from cold to warm
|
No airflow
|
Minimum airflow from cold to warm
|
Airflow from cold to warm
|
Minimum airflow from cold to warm
|
If any of these positions do not produce correct results, perform the following diagnostic procedure.
Step | Operation | Values | Yes | No |
1 |
Make sure the customer's complaint is validated.
Are the customer's complaints validated?
|
- |
Go to operation 2
|
System OK
|
2 |
Is everything connected correctly?
|
-
|
Go to operation 4
|
Go to operation 3
|
3 |
Repair if necessary.
Has the renovation been completed?
|
-
|
System OK
|
-
|
4 |
Does the damper move easily throughout the travel and does it close at both ends of the travel?
|
-
|
Go to operation 5
|
Go to operation 3
|
5 |
Check the actuator travel by turning the governor knob while the engine is running.
Is the drive stroke OK?
|
-
|
Go to operation 6
|
Jump to Operation 7
|
6 |
Is the system functioning correctly?
|
-
|
System OK
|
Go to operation 9
|
7 |
Are there any problems with the vacuum hose or actuator?
|
-
|
Jump to operation 8
|
Go to operation 9
|
8 |
If necessary, repair the vacuum hose or control actuator.
Has the renovation been completed?
|
-
|
System OK
|
Go to operation 9
|
9 |
Retest the system according to the test procedures "Position of controls/correct results" in this section.
Has the renovation been completed?
|
-
|
System OK
|
Jump to operation 10
|
10 |
Check airflow from defroster openings or vents.
Is there strong airflow from the defroster openings or vents?
|
-
|
Go to operation 11
|
Go to operation 12
|
11 |
Adjust floor heater damper and ventilation damper to obtain normal air flow.
Has the renovation been completed?
|
-
|
System OK
|
-
|
12 |
Set the mode switch to the defrost position.
Is the defroster air flow OK?
|
-
|
Jump to operation 13
|
Go to operation 14
|
13 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
14 |
Check the change in air flow at different fan speeds.
Does the fan speed increase when switching from position 1 to position 4?
|
-
|
Go to operation 15
|
|
15 |
Has the renovation been completed?
|
-
|
System OK
|
Jump to operation 16
|
16 |
Does the airflow change?
|
-
|
Go to operation 17
|
Go to operation 18
|
17 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
18 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
Too much heat
Step | Operation | Values | Yes | No |
1 |
Make sure the customer's complaint is validated.
Are the customer's complaints validated?
|
-
|
Go to operation 2
|
System OK
|
2 |
Is the heating too strong when the mode switch is set to the floor position?
|
-
|
Go to operation 3
|
Go to operation 9
|
3 |
Is there any unwanted air flow from the defrost system?
|
-
|
Go to operation 4
|
Go to operation 5
|
4 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
5 |
Is the airflow strong?
|
-
|
Go to operation 6
|
Jump to operation 8
|
6 |
Check the change in air flow at different fan speeds.
Does the airflow change as the fan speed changes?
|
-
|
Go to operations 7
|
|
7 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
8 |
Adjust or repair the system in mode "floor/window heating" and/or "ventilation/floor".
Has the renovation been completed?
|
-
|
System OK
|
-
|
9 |
Is there any unwanted air flow in the position "ventilation"?
|
-
|
Jump to operation 10
|
Jump to operation 15
|
10 |
Have problems been found?
|
-
|
Go to operation 11
|
Go to operation 12
|
11 |
If necessary, repair the system housing or floor outlet mounting.
Has the renovation been completed?
|
-
|
System OK
|
Go to operation 12
|
12 |
Do you hear the shutter click just before the regulator reaches the stop?
|
-
|
Jump to operation 13
|
Go to operation 14
|
13 |
Adjust the ventilation damper to a larger opening.
Has the renovation been completed?
|
-
|
System OK
|
-
|
14 |
Is the temperature flap working properly?
|
-
|
System OK
|
-
|
15 |
Exhaust air is warmer than intake air by more than 5°C (41°F)?
|
-
|
Jump to operation 16
|
System OK
|
16 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
Governing bodies
Step | Operation | Values | Yes | No |
1 |
Make sure the customer's complaint is validated.
Are the customer's complaints validated?
|
-
|
Go to operation 2
|
System OK
|
2 |
Operate the controls, except for the temperature controller.
Is excessive force required to move the controls?
|
-
|
Go to operation 15
|
Go to operation 3
|
3 |
Move the temperature controller.
Is excessive force required to move the controls?
|
-
|
Go to operation 6
|
Go to operation 4
|
4 |
Move the temperature controller.
Does the temperature flap move too easily?
|
-
|
Go to operation 5
|
System OK
|
5 |
Disconnect the cable from the regulator.
Does the adjuster knob turn freely without any clicks from the detent?
|
-
|
Go to operation 15
|
-
|
6 |
Check the cables for proper routing, kinks, rubbing on wiring or other parts of the instrument panel.
Have problems been found?
|
-
|
Jump to Operation 7
|
Jump to operation 8
|
7 |
Repair if necessary.
Has the renovation been completed?
|
-
|
System OK
|
-
|
8 |
Is the damper sticking?
|
-
|
Go to operation 9
|
Go to operation 12
|
9 |
Check the sticking flap for correct shaft position, bent shaft or warped housing.
Is the damper seal OK?
|
-
|
Jump to operation 10
|
Go to operation 11
|
10 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
11 |
Repair damper seal if necessary.
Has the renovation been completed?
|
-
|
System OK
|
-
|
12 |
Check regulator for sticking.
Is the regulator stuck?
|
-
|
Go to operation 14
|
Jump to operation 13
|
13 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
14 |
Is the regulator stuck?
|
-
|
Go to operation 15
|
Jump to operation 16
|
15 |
Replace regulator.
Has the renovation been completed?
|
-
|
System OK
|
-
|
16 |
Replace rope.
Has the renovation been completed?
|
-
|
System OK
|
-
|
Fan noise
Step | Operation | Values | Yes | No |
1 |
Make sure the customer's complaint is validated.
Are the customer's complaints validated?
|
-
|
Go to operation 2
|
System OK
|
2 |
Is there continuous noise at high fan speed or in certain modes, but not at low speed or in other modes?
|
-
|
Go to operation 11
|
Go to operation 3
|
3 |
Check for vibration of the motor or fan assembly at each fan speed by feeling the fan housing.
Is there excessive vibration?
|
-
|
Go to operation 6
|
Go to operation 4
|
4 |
Are foreign objects found in the fan inlet?
|
-
|
Go to operation 5
|
Go to operation 6
|
5 |
Remove all foreign objects.
Has the renovation been completed?
|
-
|
System OK
|
Go to operation 6
|
6 |
Is there any fault found?
|
-
|
Jump to Operation 7
|
Go to operation 9
|
7 |
Repair if necessary.
Has the renovation been completed?
|
-
|
System OK
|
Jump to operation 8
|
8 |
Replace motor and fan assembly.
Has the renovation been completed?
|
-
|
System OK
|
Go to operation 9
|
9 |
If the noise is clicking/ticking or howling, replace the motor.
Has the renovation been completed?
|
-
|
System OK
|
Jump to operation 10
|
10 |
Reinstall the original motor.
Does the problem reappear?
|
-
|
Go to operation 11
|
System OK
|
11 |
Is the noise present only when the windows are heated?
|
-
|
Go to operation 12
|
Jump to operation 13
|
12 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
13 |
Is the noise present only in floor blowing mode?
|
-
|
Go to operation 12
|
Go to operation 14
|
14 |
Is the noise present only in ventilation mode?
|
-
|
Go to operation 15
|
Jump to operation 16
|
15 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
16 |
Is there noise in all modes, but not in all positions of the temperature controller?
|
-
|
Go to operation 17
|
Go to operation 18
|
17 |
Has the renovation been completed?
|
-
|
System OK
|
-
|
18 |
Has the renovation been completed?
|
-
|
System OK
|
Go to operation 2
|