Lincoln 2006 Town Car Workshop Manual page 36

2006 Town Car Workshop Manual
is delivered to the blower motor through circuit 371 (PK/WH). Ground for the motor is provided through circuit 515 (OG/RD) from the blower control module. Ground for the blower control
module is provided by circuit 57 (BK).
The blower motor control module receives a 1-2 volt signal from the EATC module through circuit 752 (YE/RD) to determine the desired blower motor speed. The EATC module receives a
feedback voltage from the blower motor control module through circuit 260 (RD/OG) to determine actual blower motor speed. When the highest blower motor setting is selected, the EATC
module sends 12 volts to the blower control module through circuit 754 (LG/WH).
Possible Causes
Fuse
An open in circuits 57 (BK), 181 (BN/OG), 515 (OG/RD), 371 (PK/WH) or 754 (LG/WH)
A short to ground in circuit 754 (LG/WH)
A short to voltage in circuit 364 (BK/LG)
Blower motor
Blower motor relay
Blower motor control module
Electronic automatic temperature control (EATC) module
PINPOINT TEST M: THE BLOWER MOTOR IS INOPERATIVE
M1 VERIFY THE BLOWER MOTOR OPERATION
Ignition ON.
Press the PANEL button on the EATC module. Adjust the blower motor setting to LO and then to HI.
Is the blower motor inoperative in all settings?
M2 CHECK FOR VOLTAGE TO THE BLOWER MOTOR
Ignition OFF.
Disconnect: Blower Motor C1031.
Ignition ON.
Measure the voltage between blower motor C1031-1, circuit 371 (PK/WH) and ground.
Is the voltage greater than 10 volts?
M3 CHECK THE BLOWER MOTOR
Ignition OFF.
Connect: Blower Motor C1031.
Disconnect: Blower Motor Speed Control C1308.
Connect a fused jumper lead between blower motor speed control C1308-4, circuit 515 (OG/RD) and
C1308-5, circuit 57 (BK).
Ignition ON.
Does the blower motor operate?
M4 CHECK CIRCUIT 57 (BK) FOR AN OPEN
Ignition OFF.
Remove the fused jumper lead from the blower motor speed control C1308.
Measure the resistance between blower motor speed control C1308-5, circuit 57 (BK) and ground.
Is the resistance less than 5 ohms?
M5 CHECK CIRCUIT 515 (OG/RD) FOR AN OPEN
http://www.fordtechservice.dealerconnection.com/pubs/content/~WS6G/~MUS~LEN/19/...
Test Step Result / Action to Take
Yes
GO to M2.
No
GO to Pinpoint Test N.
Yes
GO to M3.
No
GO to M8.
Yes
GO to M6.
No
GO to M4.
Yes
GO to M5.
No
REPAIR circuit 57 (BK) for an open. TEST the system for
normal operation.
Page 36 of 45
12/30/2011