FORD MUSTANG 2003 Workshop Manual

z
Is the rear window defrost switch indicator ON? (BR/LB). TEST the system
for normal operation.
H11 CHECK ICM OUTPUT
z
Trigger the ICM active command R DEFRLY to ON.
z Measure the resistance between the heated rear window
relay pin 85, circuit 727 (YE/BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
GO to
H13 .
No
GO to H12 .
H12 CHECK CIRCUIT 727 (YE/BK) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between ICM C220a pin 10, circuit
727 (YE/BK), harness side and the heated rear window relay
pin 85, circuit 727 (YE/BK) , harness side.
z Is the resistance less than 5 ohms? Yes
GO to
H16 .
No
REPAIR the circuit. TEST
the system for normal
operation. H13 CHECK POWER TO REAR WINDOW DEFROST SWITCH
z
Disconnect: Rear Window Defrost Switch C241.
z Key in ON position.
z Measure the voltage between the rear window defrost switch
C241 pin 1, circuit 883 (PK/LB), harness side and ground. Yes
GO to
H14 .
No
REPAIR the supply circuit.
TEST the system for
normal operation. Klj . 28 ba
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z
Is the voltage greater than 10 volts? H14 CHECK INPUT TO THE ICM
z
Connect: Rear Window Defrost Switch C241.
z Depress the rear window defrost switch to ON.
z Measure the voltage between ICM C220a pin 9, circuit 175
(BK/YE), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
H16 .
No
GO to H15 .
H15 CHECK CIRCUIT 175 (BK/YE) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between ICM C220a pin 9, circuit
175 (BK/YE), harness side and the rear window defrost
switch C241 pin 2, circuit 175 (BK/YE) , harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new rear
window defrost switch.
REFER to
Rear Window Defrost Switch in this
section. TEST the system
for normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation. H16 CHECK THE ICM FOR CORRECT OPERATION
z
Disconnect all ICM connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all ICM connectors and make sure they seat
correctly.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new ICM.
REFER to
Section 413 - 01 .
CLEAR the DTCs.
REPEAT the self- test.
No
The system is operating
correctly at this time.
Concern may have been Klj . 29 ba
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PINPOINT TEST I: THE DEFROST SYSTEM WILL NOT SHUT OFF
AUTOMATICALLY caused by a loose or
corroded connector.
CLEAR the DTCs.
REPEAT the self-
test. Test Step Result / Action to Take
I1 CHECK CIRCUIT 727 (YE/BK)
z
Disconnect: Heated Rear Window Relay.
z Key in ON position.
z Depress the rear window defroster switch to OFF.
z Measure the resistance between heated rear window
relay pin 85, circuit 727 (YE/BK) , harness side and
ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
I3 .
No
GO to I2 .
I2 CHECK CIRCUIT 727 (YE/BK) FOR A SHORT TO
GROUND z
Key in OFF position.
z Measure the resistance between instrument cluster
module (ICM) C220a pin 10, circuit 727 (YE/BK) ,
harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
I4 .
No
REPAIR the circuit. TEST the
system for normal operation. I3 CHECK CIRCUIT 186 (BN/LB) FOR A SHORT TO POWER
z
Disconnect: Heated Rear Window Grid Power Supply
Connector C402a.
z Measure the voltage between heated rear window grid
C402a circuit 186 (BN/LB), harness side and ground. Yes
REPAIR the circuit. TEST the
system for normal operation.
No
INSTALL a new heated rear
window relay. TEST the
system for normal operation. Klj . 30 ba
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Component Tests
Grid Wire Test
1. Using a bright lamp inside the vehicle, inspect the wire grid from the exterior. A broken grid wire will appear as a brown spot.
2. Run the engine at idle. Set the rear window defrost switch to ON. The indicator light should come on.
3. Working from the interior of the vehicle with a voltmeter, contact the broad red- brown stripes of
the rear glass window positive lead to battery side and negative lead to ground side. The meter
should read 10- 13 volts. A lower voltage reading indicates a loose ground connection.
4. Contact a good ground point with the negative lead of the meter. The voltage reading should not differ.
5. With the negative lead of the meter grounded, touch each grid line of the heated rear window glass at its midpoint with the positive lead. A reading of approximately 6 volts indicates that the
line is good. A reading of zero volts indicates that the line is broken between the midpoint and
the B+ side of the grid line. A reading of 12 volts indicates that the circuit is broken between the
midpoint of the grid line and ground. z
Is the voltage greater than 10 volts? I4 CHECK THE ICM FOR CORRECT OPERATION
z
Disconnect all ICM connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all ICM connectors and make sure they seat
correctly.
z Operate the system and verify the concern is still
present.
z Is the concern still present? Yes
INSTALL a new ICM. REFER
to Section 413
- 01 . CLEAR the
DTCs. REPEAT the self-test.
No
The system is operating
correctly at this time. Concern
may have been caused by a
loose or corroded connector.
CLEAR the DTCs. REPEAT
the self- test. Klj . 31 ba
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Klj . 32 ba
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GENERAL PROCEDURES
Heated Window Grid Wire Repair
1. NOTE: A single break or any breaks which exceed 25 mm (1 inch) in one grid cannot be
repaired. Install a new rear window glass.
NOTE: If the first layer of the heated rear window grid (brown) is damaged or missing, it will be
necessary to apply touch- up paint on the glass prior to applying the silver rear window defroster
repair.
Repair any inoperative grid wires using rear window defroster repair.
2. Bring the vehicle up to room temperature of at least 16° C (60° F) or above.
3. Clean the entire grid line repair area with a non- alcohol based window cleaner and 0000 steel
wool.
4. Mark the location of the grid break on the exterior of the rear window glass.
SECTION 501-
11: Glass, Frames and Mechanisms 2003 Mustang Workshop Manual Material
Item Specification
Dark Walnut Metallic Acrylic
Lacquer Touch-
up Paint
ALBZ- 19500-5858A or
equivalent ESR-
M2-P100-
C Rear Window Defroster Repair
D8AZ-
19562- AA or equivalent WSB-
M4J58- B Klj . 1 ba
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5. Using cellulose tape, mask the area directly above and below the grid break. The break area
should be at the center of the mask.
6. NOTE: If the brown layer is not broken or missing, apply only the silver grid repair compound to
the break.
NOTE: If both the brown and silver layers of the grid are broken or missing, apply a coating of
the brown touch- up paint across the break in the grid line first. Do not overlap the silver grid line
with the brown paint . Several applications may be necessary to achieve a color match.
NOTE: Extend the silver repair coating at least 6.35 mm (0.25 inch) on both sides of the break
area.
NOTE: Allow at least five minutes of drying time between applications.
Apply the repair coating to the grid break area in several smooth, continuous strokes.
Apply three applications of the grid repair compound.
7. After five minutes or after the repair area has dried completely, remove the mask.
8. CAUTION: Be careful not to damage the grid line with the razor blade. If this occurs,
additional repair may be necessary.
Remove any excess repair compound above or below the grid line with a razor blade.
9. NOTE: The repair coating will air- dry in approximately one minute and can be energized within
three minutes.
NOTE: Optimum adhesion occurs after approximately 24 hours.
After optimum hardness is achieved, clean the repaired area with a non- alcohol based window
cleaner. Klj . 2 ba
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Klj . 3 ba
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GENERAL PROCEDURES
Lead Terminal Repair
1. NOTE: The rear window glass must be at room temperature at the time of the repair.
Clean the bus bar in the area to be repaired with steel wool (3/0 to 4/0 grade).
2. NOTE: Allow 10 minutes of drying time between the coats.
Apply three coats of rear window defroster repair to the surface.
3. CAUTION: Do not overheat the rear window glass or damage to the rear window
glass may occur.
SECTION 501-
11: Glass, Frames and Mechanisms 2003 Mustang Workshop Manual Special Tool(s)
Heat Gun
107-
R0300 or equivalent
Material Item Specification
Rear Window Defroster Repair
D8AZ-
19562- AA WSB-
M4J58- B Klj . 1 ba
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Tin the bus bar repair area with solder.
4. CAUTION: To prevent overheating the rear window glass, remove the soldering gun
as soon as the solder flows.
Preheat the rear window glass in the area to be repaired using the special tool and solder the
terminal to the bus bar.
5. NOTE: Turn the heated rear window switch ON for five minutes prior to the final inspection of
the repair.
Apply rear window defroster repair to the area as needed. Klj . 2 ba
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