Ford Falcon. Manual - part 415

501-09-7 

Rear View Mirrors 

501-09-7

DIAGNOSIS AND TESTING (Continued)

C94

Pin Number(s)

Circuit Designation/Description

Normal Condition/Measurement

1

Circuit 540A (R)

0 voltage, less than 5 ohms between power

mirror switch and left front mirror motor

2

Circuit 541 (L)

0 voltage, less than 5 ohms between power

Mirror x direction control

mirror switch and left front mirror motor

3

Circuit 544 (V)

0 voltage, less than 5 ohms between power

Mirror y direction control

mirror switch and left front mirror motor

C377

Pin Number(s)

Circuit Designation/Description

Normal Condition/Measurement

1

Circuit 540A (R)

0 voltage, less than 5 ohms between power

mirror switch and left front mirror motor

2

Circuit 541 (L)

0 voltage, less than 5 ohms between power

Mirror x direction control

mirror switch and left front mirror motor

3

Circuit 544 (V)

0 voltage, less than 5 ohms between power

Mirror y direction control

mirror switch and left front mirror motor

Pinpoint Tests

STANDARD MIRROR (NON MEMORY)

PINPOINT TEST A : THE MIRRORS ARE INOPERATIVE

Test Step

Result / Action to Take

A1

CHECK CIRCUIT 299 (V/R) FOR VOLTAGE

Disconnect Exterior Mirror Control Switch.

Yes

Go to A2.

Key in ON position.

No

Measure voltage between exterior mirror control switch Connector

REPAIR the circuit. TEST the system for normal

C88, Circuit 299 (V/R), harness side and ground.

operation.

Is the voltage greater than 10 volts?

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501-09-8 

Rear View Mirrors 

501-09-8

DIAGNOSIS AND TESTING (Continued)

Test Step

Result / Action to Take

A2

CHECK CIRCUIT 57 B/F (B) FOR AN OPEN

Measure the resistance between exterior mirror control switch

Yes

Connector C88, Circuit 57(B/F), harness side and ground.

Go to A3.

Is the resistance less than 5 ohms?

No

REPAIR the circuit. TEST the system for normal
operation.

A3

CHECK CIRCUIT 540 (R) FOR OPEN

Disconnect Inoperative Exterior Rear View Mirror/s C520.

Yes

INSTALL a new exterior mirror control switch.

Measure the resistance between inoperative rear view mirror

TEST the system for normal operation.

Connector (C86/C94/C377) and mirror control switch Connector C88,
Circuit 540 (R).

No

REPAIR the circuit. TEST the system for normal

Is the resistance less than 5 ohms?

operation.

PINPOINT TEST B : A SINGLE MIRROR IS INOPERATIVE

Test Step

Result / Action to Take

B1

CHECK CIRCUITS 541 (L) AND 544 (V) FOR VOLTAGE

Disconnect Inoperative Exterior Rear View Mirror Connector.

Yes

Go to A3.

Key in ON position.

No

Select the inoperative mirror on the exterior mirror control switch.

Go to B2.

Measure the voltage between the inoperative exterior rear view mirror
connector, harness side and ground while operating the exterior
mirror control switch to the specified direction.

Driver mirror

Passenger mirror

Mirror control

direction

C86 circuit 541

C94/C377 circuit

UP

541

C86 circuit 544

C94/C377 circuit

RIGHT

544

Are the voltages greater than 10 volts?

B2

CHECK FOR AN OPEN CIRCUIT

Key in OFF position.

Yes

INSTALL a new exterior mirror control switch.

Disconnect Exterior Mirror Control Switch C88.

TEST the system for normal operation.

Measure the resistance between the inoperative exterior rear view

No

mirror connector, harness side and exterior mirror control switch

REPAIR the suspect circuit. TEST the system

connector, harness side.

for normal operation.

Circuit

Driver

541 A (L)

544 A (V)

Passenger

544 B (V)

541 B (L)

Are all of the resistances less than 5 ohms?

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501-09-9 

Rear View Mirrors 

501-09-9

DIAGNOSIS AND TESTING (Continued)

Test Step

Result / Action to Take

B3

CHECK CIRCUIT 540 (R) FOR OPEN

Disconnect Inoperative Exterior Rear View Mirror/s.

Yes

INSTALL a new exterior rear view mirror. Refer

Measure the resistance between the inoperative exterior rear view

to Exterior Mirror in this section. TEST the

mirror connector, circuit 540 (R), harness side and exterior mirror

system for normal operation.

control switch C88, circuit 540 (R), harness side.

No

Is the resistance less than 5 ohms?

REPAIR the circuit. TEST the system for normal
operation.

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501-09-10 

Rear View Mirrors 

501-09-10

DIAGNOSIS AND TESTING (Continued)

PINPOINT TEST C : A SINGLE MIRROR DOES NOT FUNCTION WITH SWITCH LOGIC

Test Step

Result / Action to Take

C1

CHECK FOR THE CORRECT INPUT TO THE EXTERIOR REAR

VIEW MIRROR

Disconnect Inoperative Exterior Rear View Mirror.

Yes

INSTALL a new exterior rear view mirror. Refer

Key in ON position.

to Exterior Mirror in this section. TEST the
system for normal operation.

Select the inoperative exterior rear view mirror on the exterior mirror
control switch.

No

Measure the voltage or resistance between the suspect exterior rear

Go to C2.

view mirror connector, harness side and ground while operating the
exterior mirror control switch to the specified position. Refer to the
following chart:

Exterior

Circuit

Mirror

Measurement

mirror

control

Connector

position

Driver

C86

540 A

Down

Greater than

10 volts

C86

540 A

Up

Less than 50

ohms

C86

540 A

Right

Greater than

10 volts

C86

540 A

Left

Less than 50

ohms

Driver and Passenger

C86/C94/C377

541 A/B

Up

Greater than

10 volts

C86/C94/C377

541 A/B

Down

Less than 50

ohms

C86/C94/C377

541 A/B

Left

Greater than

10 volts

C86/C94/C377

541 A/B

Right

Less than 50

ohms

Passenger

C94/C377

540 B

Down

Greater than

10 volts

C94/C377

540 B

Up

Less than 50

ohms

C94/C377

544 B

Right

Greater than

10 volts

C94/C377

544 B

Left

Less than 50

ohms

Are the measurements as indicated?

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