A/C - Erratic Blower Operation During Maneuvering
TSB 04-14-1107/26/04
ERRATIC CLIMATE CONTROL BLOWER MOTOR
OPERATION DURING BRAKING, TURNING OR
ACCELERATION
LINCOLN:
2003-2004 Town Car
This article supersedes TSB 03-8-4 to update the vehicle model years.
ISSUE
Some 2003-2004 Lincoln Town Cars built before 4/1/2004 may exhibit erratic operation of the climate control blower motor intermittently. Symptoms may include blower motor operating at high speed uncommanded, and/or unable to control blower motor speed using the dual electronic automatic temperature control (DEATC) system. These symptoms may only be present during aggressive braking, turning and acceleration. This could be caused by chafing of the blower motor speed control wire harness (19C603) behind the right engine cam cover at the starter cable bracket near the evaporator case.
ACTION
Install revised blower motor speed control wire harness. Refer to the following Service Procedure for details.
SERVICE PROCEDURE
1. Inspect the blower motor wire harness behind the right engine cam cover at the starter cable bracket, near the evaporator case. If the wire harness is chafed proceed to Step 2. If the harness is not chafed do not continue with this TSB, refer to Workshop Manual Section 412-02 for diagnostics.
2. Disconnect the battery.
3. Lift the vehicle on a hoist. Refer to Workshop Manual, Section 100-01.
4. Unplug all four (4) oxygen sensor wire connectors.
5. Remove both right and left side catalytic converter to exhaust manifold nuts and allow the exhaust to hang.
6. Reach up between the bulkhead and the right rear of the engine and remove the 8 mm screw securing the 19C603 wire harness to the evaporator case.
7. Unplug C1308 from the blower motor speed control.
8. Lower the vehicle.
9. Unplug C1361 from the engine compartment temperature sensor, located near the engine on the evaporator case.
10. Unplug C1031 from the blower motor. To gain access to the blower motor connector, follow the Blower Motor Removal procedure found in Workshop Manual, Section 412-02. Do not remove the blower motor.
11. Remove the two (2) screws securing the wire harness to the evaporator case.
12. Disconnect the christmas tree retainer from C263 and unplug the in-line connector. Refer to Wiring Diagrams Manual, Section 151-4.
13. Remove the 19C603 wire harness.
14. Position the new wire harness (3W1Z-19C603-BA) in the vehicle. Start by routing C1308 between the two (2) heater hoses at the right rear of the engine near the heater core inlet tubes (Figure 1).
15. Direct the wire harness down the back of the engine, on the driver side of the blower motor speed control (toward center of engine compartment). Allow enough length to make the connection to the blower motor speed control.
16. Connect C1361 to the engine compartment temperature sensor.
17. Route the wire harness across the engine compartment towards the blower motor. Follow exact routing as displayed in (Figure 2).
18. Connect C1031 to the blower motor.
19. Slip the retainer on blower motor wire harness take out over the evaporator case stud (Figure 3).
20. Route the main section of the 19C603 wire harness between the two (2) mounting bosses on the evaporator case (Figure 3).
21. Using one (1) of the screws removed in Step 12, secure the wire harness retainer (nearest C263) to the top mounting boss. The other original screw is no longer used (Figure 3).
22. Connect C263, and secure the christmas tree fastener.
23. Install the blower motor insulator, RH fender apron and the windshield washer reservoir.
24. Raise the vehicle.
25. Check that the wire harness is routed down the driver side of the blower motor speed control (toward center of engine compartment). Connect C1308 to the blower motor speed control.
26. Install the exhaust using new fasteners (W705443-S900). Torque fasteners to 40 N.m (30 Lb-ft).
27. Connect all four (4) oxygen sensors.
28. Lower the vehicle and check that all blower motor speeds operate correctly.
Parts Block
WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
OPERATION DESCRIPTION TIME
041411A Install Revised Blower 1.1 Hrs.
Motor Speed Control Wire
Harness
DEALER CODING
CONDITION
BASIC PART NO. CODE
19C603 43
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