Press each steering wheel auxiliary control switch and compare the resistance reading to
the chart below.
Are the resistance readings within the range?
Switch
Resistance (ohms)
TEMP UP
379-387
TEMP DOWN
1695-1730
NO FUNCTION
4468-4558
No
INSTALL a new steering wheel auxiliary control switch. CLEAR the DTCs.
REPEAT the self-test. TEST the system for normal operation.
G3 CHECK CIRCUIT 1070 (BN/LB) FOR A SHORT TO GROUND
Disconnect: Steering Wheel Control Switch.
Measure the resistance between EATC module C228b-7, circuit 1070 (BN/LB) and ground.
Is the resistance reading less than 10,000 ohms?
Yes
REPAIR circuit 1070 (BN/LB) for a short to ground. CLEAR the DTCs. REPEAT
the self-test. TEST the system for normal operation.
No
INSTALL a new steering wheel auxiliary control switch. CLEAR the DTCs.
REPEAT the self-test. TEST the system for normal operation.
G4 CHECK CIRCUIT 1070 (BN/LB) FOR AN OPEN
Disconnect: Steering Wheel Auxiliary Control Switch.
Measure the resistance between EATC module C228b-7, circuit 1070 (BN/LB) and
steering wheel auxiliary control switch C2208-6, circuit 1070 (BN/LB).
Is the resistance less than 5 ohms?
Yes
GO to
G5
.
No
REPAIR circuit 1070 (BN/LB) for an open. CLEAR the DTCs. REPEAT the self-
test. TEST the system for normal operation.
G5 CHECK CIRCUIT 57 (BK) FOR AN OPEN
Measure the resistance between steering wheel auxiliary control switch C2208-3, circuit 57
(BK) and ground.
Is the resistance less than 5 ohms?
Yes
INSTALL a new steering wheel auxiliary control switch. CLEAR the DTCs.
REPEAT the self-test. TEST the system for normal operation.
No
REPAIR circuit 57 (BK) for an open. CLEAR the DTCs. REPEAT the self-test.
TEST the system for normal operation.
G6 CHECK MODULE CONNECTION
Carry out the Electronic Automatic Temperature Control (EATC) Module Cold Boot
Process.
Carry out the EATC on-demand self test.
Operate the system.
Does the concern return?
Yes
INSTALL a new EATC module. REFER to
Section 412-01
. TEST the system for
normal operation.
No
The system is operating correctly at this time. The concern may have been
caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-
test. TEST the system for normal operation.
Page 26 of 45
2006 Town Car Workshop Manual
12/30/2011
http://www.fordtechservice.dealerconnection.com/pubs/content/~WS6G/~MUS~LEN/19/...