DESCRIPTION
for Manual Air Conditioning System:
When the rear window defogger switch, which is built into the heater control, is operated, operation signals are transmitted to the DEF relay coil . When the DEF relay coil receives the signals, the DEF relay switch turns on to operate the rear window defogger.
for Automatic Air Conditioning System:
When the rear window defogger switch is turned on, a rear window defogger activation request signal is sent via the LIN communication line to the air conditioning amplifier. Then the air conditioning amplifier operates the rear window defogger. When the on signal from the switch is received, the DEF relay is operated for 15 minutes. Also, if the off signal from the switch is received within 15 minutes, the DEF relay operation is stopped.
INSPECTION PROCEDURE
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
READ VALUE USING INTELLIGENT TESTER (Battery Voltage Lo Record)
Using the intelligent tester, inspect battery voltage reduction history "Battery Voltage Lo Record" in the Data List.
| Tester Display | Measurement item/Range | Normal Condition | Diagnostic Note |
|---|---|---|---|
| Battery Voltage Lo Record | Battery voltage reduction history/ Min.: 0 times, Max.: 65535 times | 0 to 65535 | - |
| Result | Proceed to |
|---|---|
| Other than 0 (history record is present) | A |
| 0 (no history record is present) | B |
CHECK AIR CONDITIONING SYSTEM TYPE
Check the air conditioning system type.
| Result | Proceed to |
|---|---|
| Automatic Air Conditioning System | A |
| Manual Air Conditioning System | B |
CHECK FOR DTC
Check for DTCs.
| Result | Proceed to |
|---|---|
| DTC is not output | A |
| LIN DTC is output | B |
PERFORM ACTIVE TEST USING INTELLIGENT TESTER (DEF RELAY)
Select the Active Test using the intelligent tester to generate a control command, and then check that the rear window defogger operates.
| Tester Display | Test Part | Control Range | Diagnostic Note |
|---|---|---|---|
| Defogger Relay (Rear) | Rear window defogger relay operation | OFF/ON | - |
Check that operation sound of the DEF relay is heard.
| Result | Proceed to |
|---|---|
| The window defogger system operates normally when operating it through the intelligent tester. | A |
| The window defogger system does not operate normally when operating it through the intelligent tester and DEF relay operating sound is not heard. | B |
| The window defogger system does not operate normally when operating it through the intelligent tester and DEF relay operating sound is heard. | C |
REPLACE AIR CONDITIONING CONTROL ASSEMBLY
Temporarily replace the air conditioning control assembly with a new or normally functioning one (Click here).
CHECK WINDOW DEFOGGER SYSTEM
Turn the ignition switch to ON.
Check that pressing the defogger switch illuminates the indicator and warms the rear window surface.
Check that after approximately 15 minutes, the indicator light turns off and the rear window defogger deactivates.
| OK |
|---|
| Rear window defogger system is functioning normally. |
CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY)
Disconnect the DG main body ECU connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
| *1 | Front view of wire harness connector (to Main Body ECU) |
| Result | Proceed to |
|---|---|
| OK (for Automatic Air Conditioning System) | A |
| OK (for Manual Air Conditioning System) | B |
| NG | C |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - MAIN BODY ECU)
Disconnect the DQ main body ECU connector.
Disconnect the H46 air conditioning amplifier connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
| *1 | Front view of wire harness connector (to Air Conditioning Amplifier) |
| *2 | Front view of wire harness connector (to Main Body ECU) |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - BATTERY)
Reconnect the H46 air conditioning amplifier connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
| *1 | Front view of wire harness connector (to Air Conditioning Amplifier) |
CHECK HARNESS AND CONNECTOR (HEATER CONTROL - MAIN BODY ECU)
Disconnect the DQ main body ECU connector.
Disconnect the H65 heater control connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| *1 | Front view of wire harness connector (to Heater Control) |
| *2 | Front view of wire harness connector (to Main Body ECU) |
CHECK HARNESS AND CONNECTOR (HEATER CONTROL - BATTERY AND BODY GROUND)
Reconnect the H65 heater control connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | |||||||
|---|---|---|---|---|---|---|---|
|
| *1 | Front view of wire harness connector (to Heater Control) |
CHECK HARNESS AND CONNECTOR (BACK DOOR GLASS - MAIN BODY ECU AND BODY GROUND)
Disconnect the DF main body ECU connector.
Disconnect the S1 and S2 rear window defogger wire connectors.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
| *1 | Front view of wire harness connector (to Main Body ECU) |
*2 | Front view of wire harness connector (to Back Door Glass) |
CHECK HARNESS AND CONNECTOR (WINDOW DEFOGGER WIRE)
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
| *1 | Front view of wire harness connector (to Back Door Glass) |
GO TO POWER STEERING SYSTEMClick here
GO TO LIN COMMUNICATION SYSTEMClick here
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLYClick here
END (AIR CONDITIONING CONTROL ASSEMBLY IS DEFECTIVE)
REPAIR OR REPLACE HARNESS OR CONNECTOR
REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)
REPLACE BACK DOOR GLASSClick here
REPLACE HEATER CONTROL SUB-ASSEMBLYClick here