Page 1337 of 2395

When the rear window defogger switch is turned ON, ground is supplied
Ithrough terminal 2 of the rear window defogger switch (with navigation system), or
Ithrough terminal 31 of A/C auto amp. (without navigation system)
Ito smart entrance control unit terminal 39.
Terminal 2 of the smart entrance control unit then supplies ground to the rear window defogger relay termi-
nal 2.
With power and ground supplied, the rear window defogger relay is energized.
Power is supplied
Ithrough terminals 5 and 7 of the rear window defogger relay
Ito the rear window defogger.
The rear window defogger has an independent ground.
With power and ground supplied, the rear window defogger filaments heat and defog the rear window.
When the system is activated, the rear window defogger indicator illuminates in the rear window defogger
switch.
Power is supplied
Ito terminal 3 of the rear window defogger switch (with navigation system), or
Ito terminal 30 of the A/C auto amp. (without navigation system)
Ifrom terminal 7 of the rear window defogger relay.
Terminal 4 of the rear window defogger switch (with navigation system) or terminal 32 of the A/C auto amp.
(without navigation system), is grounded through body grounds M4, M66 and M147.
REAR WINDOW DEFOGGER
System Description (Cont'd)
EL-152
Page 1338 of 2395
Wiring Diagram Ð DEF ÐNBEL0074
MEL815L
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
IDX
REAR WINDOW DEFOGGER
Wiring Diagram Ð DEF Ð
EL-153
Page 1339 of 2395
MEL816L
REAR WINDOW DEFOGGER
Wiring Diagram Ð DEF Ð (Cont'd)
EL-154
Page 1340 of 2395

Trouble DiagnosesNBEL0075DIAGNOSTIC PROCEDURENBEL0075S01SYMPTOM: Rear window defogger does not activate, or does
not go off after activating.
1 CHECK REAR WINDOW DEFOGGER OUTPUT SIGNAL
1. Turn ignition switch to ON position.
2. Check voltage between smart entrance control unit harness terminal 2 and ground.
SEL384X
OK or NG
OK©Check the following.
IRear window defogger relay
(Refer to EL-157.)
IRear window defogger circuit
IRear window defogger filament
(Refer to EL-157.)
NG©GO TO 2.
2 CHECK DEFOGGER RELAY COIL SIDE CIRCUIT
1. Disconnect smart entrance control unit connector.
2. Turn ignition switch to ON position.
3. Check voltage between smart entrance control unit terminal 2 and ground.
SEL385X
OK or NG
OK©GO TO 3.
NG©Check the following.
I7.5A fuse [No. 11, located in the fuse block (J/B)]
IRear window defogger relay
IHarness for open or short between rear window defogger relay and smart entrance
control unit
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
IDX
REAR WINDOW DEFOGGER
Trouble Diagnoses
EL-155
Page 1341 of 2395
3 CHECK REAR WINDOW DEFOGGER SWITCH INPUT SIGNAL
Check continuity between smart entrance control unit terminal 39 and ground.
SEL386X
OK or NG
OK©GO TO 4.
NG©Check the following.
IRear window defogger switch (with navigation system)
(Refer to EL-157.)
IA/C auto amp. (without navigation system)
IHarness for open or short between smart entrance control unit and rear window defog-
ger switch (with navigation system) or A/C auto amp. (without navigation system)
IRear window defogger switch (with navigation system) or A/C auto amp. (without navi-
gation system) ground circuit
4 CHECK IGNITION INPUT SIGNAL
Check voltage between smart entrance control unit terminal 33 and ground.
SEL387X
OK or NG
OK©GO TO 5.
NG©Check the following.
I7.5A fuse [No. 11, located in the fuse block (J/B)]
IHarness for open or short between smart entrance control unit and fuse
REAR WINDOW DEFOGGER
Trouble Diagnoses (Cont'd)
EL-156
Page 1342 of 2395
5 CHECK SMART ENTRANCE CONTROL UNIT GROUND CIRCUIT
Check continuity between smart entrance control unit terminal 16 and ground.
SEL388X
OK or NG
OK©Replace smart entrance control unit.
NG©Repair harness or connectors.
SEC202B
Electrical Components InspectionNBEL0076REAR WINDOW DEFOGGER RELAYNBEL0076S01Check continuity between terminals 3 and 5, 6 and 7.
Condition Continuity
12V direct current supply between ter-
minals 1 and 2Ye s
No current supply No
SEL430TB
REAR WINDOW DEFOGGER SWITCHNBEL0076S02Check continuity between terminals when rear window defogger
switch is pushed and released.
Terminals Condition Continuity
1-2Rear window defogger
switch is pushedYe s
Rear window defogger
switch is releasedNo
SEL263
Filament CheckNBEL00771. Attach probe circuit tester (in volt range) to middle portion of
each filament.
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
IDX
REAR WINDOW DEFOGGER
Trouble Diagnoses (Cont'd)
EL-157
Page 1343 of 2395

SEL265
2. If a filament is burned out, circuit tester registers 0 or 12 volts.
3. To locate burned out point, move probe to left and right along
filament. Test needle will swing abruptly when probe passes
the point.
SEL122R
IWhen measuring voltage, wrap tin foil around the top of
the negative probe. Then press the foil against the wire
with your finger.
Filament RepairNBEL0078REPAIR EQUIPMENTNBEL0078S011) Conductive silver composition (Dupont No. 4817 or equivalent)
2) Ruler 30 cm (11.8 in) long
3) Drawing pen
4) Heat gun
5) Alcohol
6) Cloth
BE540
REPAIRING PROCEDURENBEL0078S021. Wipe broken heat wire and its surrounding area clean with a
cloth dampened in alcohol.
2. Apply a small amount of conductive silver composition to tip of
drawing pen.
Shake silver composition container before use.
3. Place ruler on glass along broken line. Deposit conductive sil-
ver composition on break with drawing pen. Slightly overlap
existing heat wire on both sides [preferably 5 mm (0.20 in)] of
the break.
REAR WINDOW DEFOGGER
Filament Check (Cont'd)
EL-158
Page 1344 of 2395
SEL012D
4. After repair has been completed, check repaired wire for con-
tinuity. This check should be conducted 10 minutes after silver
composition is deposited.
Do not touch repaired area while test is being conducted.
SEL013D
5. Apply a constant stream of hot air directly to the repaired area
for approximately 20 minutes with a heat gun. A minimum dis-
tance of 3 cm (1.2 in) should be kept between repaired area
and hot air outlet. If a heat gun is not available, let the repaired
area dry for 24 hours.
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
IDX
REAR WINDOW DEFOGGER
Filament Repair (Cont'd)
EL-159