Ford 2003 Mustang Workshop Manual page 3654

Is the resistance less than 5 ohms?
B6 CHECK THE LEFT/RIGHT INPUT
Measure the voltage between driver exterior rear view mirror C516
pin A, circuit 540 (RD), harness side and ground; or between
passenger exterior rear view mirror C622 pin B, circuit 543 (DG),
harness side and ground.
Actuate the exterior rear view mirror control to the left position.
Is the voltage greater than 10 volts?
B7 CHECK CIRCUIT 540 (RD) FOR AN OPEN
Disconnect: Exterior Rear View Mirror Control C527.
Measure the resistance between exterior rear view mirror control
C527 pin 4, circuit 540 (RD), harness side and driver exterior rear
view mirror C516 pin A, circuit 540 (RD), harness side.
Is the resistance less than 5 ohms?
B8 CHECK CIRCUIT 543 (DG) FOR AN OPEN
Disconnect: Exterior Rear View Mirror Control C527.
Measure the resistance between exterior rear view mirror control
C527 pin 8, circuit 543 (DG), harness side and passenger exterior
rear view mirror C622 pin B, circuit 543 (DG), harness side.
operation.
No
REPAIR the circuit.
TEST the system for
normal operation.
Yes
INSTALL a new
exterior rear view
mirror motor. REFER
to Mirror—Motor in
this section. TEST
the system for normal
operation.
No
GO to B7 for driver
inoperative or GO to
B8 for passenger
inoperative.
Yes
INSTALL a new
exterior rear view
mirror control.
REFER to Switch—
Exterior Rear View
Mirror Control in this
section. TEST the
system for normal
operation.
No
REPAIR the circuit.
TEST the system for
normal operation.
Yes
INSTALL a new
exterior rear view
mirror control.
REFER to Switch—
Exterior Rear View
Mirror Control in this
section. TEST the
system for normal