Rear View Mirror: Overview Ford Fiesta Mk6

Principles of Operation

LH and RH exterior rear view mirror glass movement is controlled by the exterior rear view mirror switch and the LH and RH exterior rear view mirror motors. Adjusting the exterior rear view mirror switch to the LH or RH position determines which exterior rear view mirror motor to control.

Normal Operation

The exterior rear view mirror switch receives voltage at all times from the Battery Junction Box (BJB). The exterior rear view mirror switch has only one ground circuit. The exterior rear view mirrors share a common circuit for both up/down and right/left movements.

This pinpoint test is intended to diagnose the following

1. Fuse
2. Wiring, terminals or connectors
3. Exterior rear view mirror switch

Scheme 1

Scheme 2

Scheme 3

1. A1 CHECK FOR VOLTAGE TO THE EXTERIOR REAR VIEW MIRROR SWITCH Disconnect: Exterior Rear View Mirror Switch C527. Measure the voltage between exterior rear view mirror switch C527-6, circuit SBB26 (YE/RD), harness side and ground. Is the voltage greater than 10 volts? Yes: Go to A2 . No: VERIFY that BJB fuse 26 (7.5A) is OK. If OK, REPAIR the circuit. If not OK, refer to the appropriate SYSTEM WIRING DIAGRAMS article to identify the possible causes of the circuit short. TEST the system for normal operation.
2. A2 CHECK FOR GROUND TO THE EXTERIOR REAR VIEW MIRROR SWITCH Measure the resistance between exterior rear view mirror switch C527-4, circuit GD143 (BK/VT), harness side and ground. Is the resistance less than 5 ohms? Yes: Go to A3 . No: REPAIR the circuit for an open. TEST the system for normal operation.
3. A3 CHECK THE EXTERIOR REAR VIEW MIRRORS COMMON CIRCUIT FOR AN OPEN Disconnect: LH Exterior Rear View Mirror Switch C521. Measure the resistance between exterior rear view mirror switch C527-3, circuit CPM18 (GN/BN), harness side and LH exterior rear view mirror C521-6, circuit CPM18 (GN/BN) harness side. Is the resistance less than 5 ohms? Yes: INSTALL a new exterior rear view mirror switch. Refer to «EXTERIOR MIRROR CONTROL SWITCH»(ref-382433-S12694554932011012300000) in this information. TEST the system for normal operation. No: REPAIR the circuit for an open. TEST system for normal operation.

Refer to appropriate SYSTEM WIRING DIAGRAMS article for schematic and connector information.

Under normal operation, the exterior rear view mirror switch uses a common circuit to control the up/down and right/left movements of both exterior rear view mirrors.

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. Exterior rear view mirror switch
3. Exterior rear view mirror motor
4. Exterior rear view mirror

Note. Use the correct probe adapter(s) from the Flex Probe Kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Scheme 4

Scheme 5

1. B1 CHECK THE LH EXTERIOR REAR VIEW MIRROR OPERATION Operate the LH exterior rear view mirror using the exterior rear view mirror switch. Does the LH exterior rear view mirror operate? Yes: Go to B2 . No: Go to B4 .
2. B2 CHECK THE EXTERIOR REAR VIEW MIRROR SWITCH Ignition OFF. Disconnect: Exterior Rear View Mirror Switch C527. Carry out the exterior rear view mirror switch component test. Refer to «REAR VIEW MIRRORS - Exterior»(ref-382433-S11631312472011012300000) and appropriate SYSTEM WIRING DIAGRAMS article for component testing. Did the exterior mirror control switch pass the component test? Yes: Go to B3 . No: INSTALL a new exterior rear view mirror switch. Refer to «EXTERIOR MIRROR CONTROL SWITCH»(ref-382433-S12694554932011012300000) in this information. TEST the system for normal operation.
3. B3 CHECK THE EXTERIOR REAR VIEW MIRRORS COMMON CIRCUIT FOR AN OPEN Disconnect: RH Exterior Rear View Mirror C601. Measure the resistance between exterior rear view mirror switch C527-3, circuit CPM18 (GN/BN), harness side and RH exterior rear view mirror C601-6, circuit CPM18 (GN/BN), harness side. Is the resistance less than 5 ohms? Yes: INSTALL a new exterior rear view mirror motor. Refer to «EXTERIOR MIRROR MOTOR»(ref-382433-S20093278102011012300000) in this information. TEST the system for normal operation. No: REPAIR the circuit for an open. TEST the system for normal operation.
4. B4 CHECK THE EXTERIOR REAR VIEW MIRROR SWITCH Ignition OFF. Disconnect: Exterior Rear View Mirror Switch C527. Carry out the Exterior Rear View Mirror Switch component test. Refer to «REAR VIEW MIRRORS - Exterior»(ref-382433-S11631312472011012300000) and appropriate SYSTEM WIRING DIAGRAMS article for component testing. Did the exterior mirror control switch pass the component test? Yes: Go to B5 . No: INSTALL a new exterior rear view mirror switch. Refer to «EXTERIOR MIRROR CONTROL SWITCH»(ref-382433-S12694554932011012300000) in this information. TEST the system for normal operation.
5. B5 CHECK THE EXTERIOR REAR VIEW MIRRORS COMMON CIRCUIT FOR AN OPEN Disconnect: LH Exterior Rear View Mirror Switch C521. Measure the resistance between exterior rear view mirror switch C527-3, circuit CPM18 (GN/BN), harness side and LH exterior rear view mirror C521-6, circuit CPM18 (GN/BN), harness side. Is the resistance less than 5 ohms? Yes: INSTALL a new exterior rear view mirror motor. Refer to «EXTERIOR MIRROR MOTOR»(ref-382433-S20093278102011012300000) in this information. TEST the system for normal operation. No: REPAIR the circuit. TEST the system for normal operation.

Refer to appropriate SYSTEM WIRING DIAGRAMS article for schematic and connector information.

Under normal operation, the exterior rear view mirror switch supplies voltage and ground to the LH and RH exterior rear view mirrors to control movement. Each mirror contains a horizontal and a vertical motor. The exterior rear view mirror switch controls movement by reversing polarity of the voltage and ground circuits being supplied to each motor.

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. Exterior rear view mirror switch
3. Exterior rear view mirror motor
4. Exterior rear view mirror

Note. Use the correct probe adapter(s) from the Flex Probe Kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

Scheme 12

Scheme 13

1. C1 CHECK THE EXTERIOR REAR VIEW MIRROR MOVEMENT (LEFT/RIGHT) Operate the RH and LH exterior rear view mirrors in the right and left direction using the exterior rear view mirror switch. Do the exterior rear view mirrors move left and right? Yes: Go to C2 . No: Go to C3 .
2. C2 CHECK THE EXTERIOR REAR VIEW MIRROR MOVEMENT (UP/DOWN) Operate the RH and LH exterior rear view mirrors in the up and down direction using the exterior rear view mirror switch. Do the exterior rear view mirrors move up and down? Yes: The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. TEST the system for normal operation. No: Go to C4 .
3. C3 CHECK THE VOLTAGE TO THE INOPERATIVE EXTERIOR REAR VIEW MIRROR LEFT/RIGHT CIRCUIT Disconnect: Inoperative Exterior Rear View Mirror C521 (LH) or C601 (RH). NOTE: Position the exterior rear view mirror switch to the LH or RH position. LH exterior rear view mirror: While operating the exterior rear view mirror switch in the rightward position, measure the voltage between the LH exterior rear view mirror C521-5, circuit CPM18 (GN/BN), harness side and ground. RH exterior rear view mirror: While operating the exterior rear view mirror switch in the rightward position, measure the voltage between the RH exterior rear view mirror C601-7, circuit CPM17 (BU/GN), harness side and ground. Is the voltage greater than 10 volts? Yes: INSTALL a new exterior rear view mirror motor. Refer to «EXTERIOR MIRROR MOTOR»(ref-382433-S20093278102011012300000) in this information. TEST the system for normal operation. No: Go to C5 .
4. C4 CHECK THE VOLTAGE TO THE INOPERATIVE EXTERIOR REAR VIEW MIRROR UP/DOWN CIRCUIT Disconnect: Inoperative Exterior Rear View Mirror C521 (LH) or C601 (RH). NOTE: Position the exterior rear view mirror switch to the LH or RH position. LH exterior rear view mirror: While operating the exterior rear view mirror switch in the upward position, measure the voltage between the LH exterior rear view mirror C521-7, circuit CPM21 (YE/VT), harness side and ground. RH exterior rear view mirror: While operating the exterior rear view mirror switch in the upward position, measure the voltage between the RH exterior rear view mirror C601-5, circuit CPM14 (GY/BN), harness side and ground. Is the voltage greater than 10 volts? Yes: INSTALL a new exterior rear view mirror motor. Refer to «EXTERIOR MIRROR MOTOR»(ref-382433-S20093278102011012300000) in this information. TEST the system for normal operation. No: Go to C6 .
5. C5 CHECK THE INOPERATIVE EXTERIOR REAR VIEW MIRROR LEFT/RIGHT CIRCUIT FOR AN OPEN Disconnect: Exterior Rear View Mirror Switch C527. LH exterior rear view mirror: Measure the resistance between exterior rear view mirror switch C527-7, circuit CPM18 (GN/BN), harness side and LH exterior rear view mirror C521-5, circuit CPM18 (GN/BN), harness side. RH exterior rear view mirror: Measure the resistance between exterior rear view mirror switch C527-5, circuit CPM17 (BU/GN), harness side and RH exterior rear view mirror C601-7, circuit CPM17 (BU/GN), harness side. Is the resistance less than 5 ohms? Yes: INSTALL a new exterior rear view mirror switch. Refer to «EXTERIOR MIRROR CONTROL SWITCH»(ref-382433-S12694554932011012300000) in this information. TEST the system for normal operation. No: REPAIR the circuit. TEST the system for normal operation.
6. C6 CHECK THE INOPERATIVE EXTERIOR REAR VIEW MIRROR UP/DOWN CIRCUIT FOR AN OPEN Disconnect: Exterior Rear View Mirror Switch C527. LH exterior rear view mirror: Measure the resistance between exterior rear view mirror switch C527-1, circuit CPM21 (YE/VT), harness side and LH exterior rear view mirror C521-7, circuit CPM21 (YE/VT), harness side. RH exterior rear view mirror: Measure the resistance between exterior rear view mirror switch C527-2, circuit CPM14 (GY/BN), harness side and RH exterior rear view mirror C601-5, circuit CPM14 (GY/BN), harness side. Is the resistance less than 5 ohms? Yes: INSTALL a new exterior rear view mirror switch. Refer to «EXTERIOR MIRROR CONTROL SWITCH»(ref-382433-S12694554932011012300000) in this information. TEST the system for normal operation. No: REPAIR the circuit. TEST the system for normal operation.

Refer to appropriate SYSTEM WIRING DIAGRAMS article for schematic and connector information for windows or mirrors.

Under normal operation, when the rear window defrost switch is pressed to the ON position, the rear window defrost relay closes and voltage is supplied to Central Junction Box (CJB) fuse 25 (7.5A) to power the LH and RH exterior rear view mirrors. The exterior rear view mirrors do not share a common ground.

This pinpoint test is intended to diagnose the following

1. Fuse
2. Wiring, terminals or connectors
3. Exterior rear view mirror glass

Scheme 14

Scheme 15

1. D1 CHECK THE OPERATION OF THE REAR WINDOW DEFROST SYSTEM With the engine running, activate the rear window defrost switch to the ON position. Using a infrared temperature gun or equivalent measure the temperature of the rear window glass for approximately 30 seconds noting changes in temperature. Does the temperature of the rear window glass rise? Yes: Go to D2 . No: Refer to «GLASS, FRAMES AND MECHANISMS»(ref-382428) to diagnose the rear window defrost system.
2. D2 CHECK THE OPERATION OF THE HEATED EXTERIOR REAR VIEW MIRRORS With the rear window defrost switch in the ON position, using a infrared temperature gun or equivalent measure the temperature of the RH and LH exterior rear view mirror glass for approximately 30 seconds noting changes in temperature. Does at least one heated mirror glass operate correctly? Yes: Go to D3 . No: VERIFY that CJB fuse 25 (7.5A) is OK. If OK, REPAIR circuit CRD06 (BN/YE) for an open. If not OK, REPAIR circuit CBP25 (WH/OG) harness side for a short to ground. TEST the system for normal operation.
3. D3 CHECK THE VOLTAGE TO THE INOPERATIVE HEATED EXTERIOR REAR VIEW MIRROR GLASS Ignition ON. Disconnect: Inoperative Heated Exterior Rear View Mirror C521(LH) or C601(RH). NOTE: The rear window defrost system activates for 10 minutes. With the engine running, press the rear window defrost switch to the ON position. Measure the voltage between: LH exterior rear view mirror C521-1, circuit CBP25 (WH/OG), harness side and ground. RH exterior rear view mirror C601-1, circuit CBP25 (WH/OG), harness side and ground. Is the voltage greater than 10 volts? Yes: Go to D4 . No: REPAIR the circuit for an open. TEST the system for normal operation.
4. D4 CHECK THE INOPERATIVE EXTERIOR REAR VIEW MIRROR GROUND CIRCUIT FOR AN OPEN Ignition OFF. Measure the resistance between: LH exterior rear view mirror C521-2, circuit GD143 (BK/VT), harness side and ground. RH exterior rear view mirror C601-2, circuit GD145 (BK/BU), harness side and ground. Is the resistance less than 5 ohms? Yes: INSTALL a new exterior rear view mirror glass. Refer to «EXTERIOR MIRROR GLASS»(ref-382433-S17900123772011012300000) in this information. TEST the system for normal operation. No: REPAIR the circuit for an open. TEST the system for normal operation.

The interior auto-dimming mirror contains 2 photoelectric sensors: one in the front of the interior rear view mirror and one mounted on the glass side of the mirror. If the sensors are blocked, the auto-dimming feature may not operate correctly. Always verify both sensors are not physically blocked before attempting to diagnose auto-dimming mirror concerns. Whenever the gear selector lever is placed in REVERSE, the interior auto-dimming mirror temporarily disables the auto-dimming feature. The auto-dimming feature is enabled again when the gear selector lever is moved out of REVERSE.

This pinpoint test is intended to diagnose the following

1. Fuse
2. Wiring, terminals or connectors
3. Obstructed rearward facing sensor
4. Obstructed forward facing sensor
5. Interior auto-dimming mirror