REAR WINDOW DEFOGGER
TSB Revision
CHASSIS ELECTRICAL
54A-237
REAR WINDOW DEFOGGER
ON-VEHICLE SERVICE
PRINTED-HEATER LINES CHECK
M1543001800139
1. Run engine at 2,000 r/min. Check heater element with
battery at full.
2. Turn "ON "rear window defogger switch. Measure heater
element voltage with circuit tester at rear window glass
centre A. Condition is good if it indicates about 6 V.
3. If 12 V is indicated at A, there is a break in the negative
terminals from A. Move test bar slowly to negative terminal
to detect where voltage changes suddenly (0V).
4. If 0 V is indicated at A, there is a break in the positive
terminals from A. Defect where the voltage changes
suddenly (12 volts, battery positive voltage) in the same
method described above.
REAR WINDOW DEFOGGER SWITCH
REMOVAL AND INSTALLATION
M1543006200217
<Vehicles with manual A/C>
Refer to GROUP 55A, Heater Control Assembly and
Blower Switch Assembly
P.55A-120
.
<Vehicles with auto A/C>
Refer to GROUP 55B, A/C Control Panel, A/C Con-
trol Unit
P.55B-142
.
INSPECTION
M1543019501835
REAR WINDOW DEFOGGER SWITCH CHECK
ACX00813
NORMAL CHARACTERSTIC CURVE
ABNORMAL CHARACTERSTIC CURVE
VOLTAGE
A (CENTER POINT)
APPROXIMATELY
6 V
NEGATIVE
TERMINAL
PRINTED
HEATER
LINE
POSITIVE
TERMINAL
NEGATIVE
TERMINAL
PRINTED
HEATER
LINE
POSITIVE
TERMINAL
OPENCIRCUIT
POINT
VOLTAGE
AC
SWITCH POSITION
TESTER
CONNECTION
SPECIFIED
CONDITION
OFF
11
− 12
Open circuit
ON
11
− 12
Less than 2 ohms
1
2
3
4
5
6
7
8
9
10 11 12
ACX02300
AC
HEATER CONTROL ASSEMBLY
CONNECTORT