Ford 2003 Mustang Workshop Manual page 3740

Disconnect: Heated Rear Window Grid Ground Connector
C402b.
Measure the resistance between heated rear window grid
C402b, circuit 1205 (BK), harness side and ground.
Is the resistance less than 5 ohms?
H8 CHECK CIRCUIT 727 (YE/BK)
Disconnect: Heated Rear Window Relay.
Depress the rear window defrost switch to ON.
Measure the resistance between heated rear window relay
pin 85, circuit 727 (YE/BK), harness side and ground.
Is the resistance less than 5 ohms?
H9 CHECK CIRCUIT 185 (BK) FOR POWER
Measure the voltage between heated rear window relay pin
86 and pin 30, circuit 185 (BK), harness side and ground.
Are the voltages greater than 10 volts?
H10 CHECK CIRCUIT 186 (BR/LB) FOR AN OPEN
Using a fused jumper wire (15A), jumper across the heated
rear window relay pin 30, circuit 185 (BK), harness side and
the heated rear window relay pin 87, circuit 186 (BR/LB),
harness side.
CARRY OUT the heated
rear window grid wire test.
REFER to Grid Wire Test
in Component Tests in this
section. TEST the system
for normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation.
Yes
GO to H9 .
No
GO to H11 .
Yes
GO to H10 .
No
REPAIR the supply circuit.
TEST the system for
normal operation.
Yes
INSTALL a new heated
rear window relay. TEST
the system for normal
operation.
No
REPAIR circuit 186