Pinpoint Test O: DTC B113E — Rear Climate Control Switch Circuit Short To Ground
Refer to Wiring Diagrams Cell
55
, Automatic Climate Control System for schematic and connector information.
Normal Operation
Under normal operation, ground is provided to the rear climate control switch through circuit 676 (PK/OG). When the switch pressed, ground through an internal resistor is sent to the rear
redundant control module (RRCM) through circuit 1349 (PK/LG).
Possible Causes
A short to ground in circuit 1349 (PK/LG)
Rear climate control switch
Rear redundant control module (RRCM)
PINPOINT TEST O: DTC B113E — REAR CLIMATE CONTROL SWITCH CIRCUIT SHORT TO GROUND
Is the voltage greater than 1 volt?
N9 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.
Test Step
Result / Action to Take
O1 CHECK CIRCUIT 1349 (PK/LG) FOR GROUND
Ignition OFF.
Disconnect: Rear Redundant Control Module (RRCM) C3160a.
Measure the resistance between RRCM C3160a-4 pin 4, circuit 1349 (PK/LG)
and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to
O2
.
No
GO to
O3
.
O2 CHECK CIRCUIT 1349 (PK/LG) FOR A SHORT TO GROUND
Disconnect: Rear Climate Control Switch C3161.
Measure the resistance between RRCM C3160a-4 pin 4, circuit 1349 (PK/LG)
and ground.
Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new rear climate control switch. CLEAR the DTCs. REPEAT the self-test. TEST
the system for normal operation.
No
REPAIR circuit 1349 (PK/LG) for a short to ground. CLEAR the DTCs. REPEAT the self-
test. TEST the system for normal operation.
O3 CHECK RRCM MODULE CONNECTION
Clear the DTCs.
Disconnect all of the RRCM connectors.
Check for:
corrosion.
pushed-out connectors.
incorrectly seated connector.
Yes
INSTALL a new RRCM. 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.
Page 41 of 45
2006 Town Car Workshop Manual
12/30/2011
http://www.fordtechservice.dealerconnection.com/pubs/content/~WS6G/~MUS~LEN/19/...
