A/C - Delayed Operation After Cold Start-Up
Article No. 86-15-3AIR CONDITIONING - EATC - DELAYED OPERATION AFTER COLD START-UP - VEHICLES BUILT PRIOR TO 5/1/86 WITH 5.0L ENGINE ONLY
FORD 1986 THUNDERBIRD
LINCOLN-MERCURY 1986 COUGAR, MARK VII LSC
The EATC system blower motor operation could be delayed for 9 to 13 minutes after cold engine start-up in cold ambient temperatures. This is due to the coolant temperature switch being located in the rear of the intake manifold. The coolant, temperature at this location is 80~F colder than the new location in the heater inlet hole.
To correct this, install a coolant temperature switch in the heater inlet hose and disconnect the engine mounted temperature switch by using the following service procedure.
All Vehicles:
1. Partially drain the coolant from the radiator.
2. Remove the inlet and outlet hoses from the heater core and the engine coolant tubes.
Figure 5:
3. Assemble inlet hoses (E4DZ-18472-D) and (E4DZ- 18472-A) to tube assembly (E5SZ-18B402-A) and secure with hose clamps (C9AZ-8287-A). (Figure 5)
4. Install coolant switch assembly (E5SZ-18D371-A) (with sealer on the threads) into the tube assembly. Tighten the switch to 8-14 ft.lbs. torque (Figure 5).
Figure 6:
5. Install the assembled tube, switch and hoses to the heater core inlet tube and engine coolant tube (Figure 6). Secure in place with two hose clamps.
6. Install a new heater return hose (E6LY-18472-C) and secure with two hose clamps (Figure 6).
Figure 7:
Mark VII Only:
A. Disconnect the existing yellow/white wire from the coolant temperature sensor at the rear of the engine and cut the connector from the end of the wire (Figure 7).
B. Splice a jumper wire (E6LY-19D570-A) to the yellow/white wire with a splice clip (E6FZ-14488- A). Insert the bare ends of each wire into the splice clip, one in each end of the clip, and crimp using an approved Ford tool. Heat shrink the plastic cover over the splice clip to ensure a good seal.
C. Connect the jumper wire electrical connector to the coolant temperature switch installed in Step 4.
D. Attach the eyelet terminal of the jumper wire at any available drill dimple near the top center of the cowl with a No. 8 drill point screw (381801-S36B).
E. Fill the cooling system and run the engine to check for coolant leaks. Then, add coolant to the cooling system as necessary.
F. Check the EATC system for proper operation, including the cold engine blower lock-out function.
Figure 8:
Thunderbird/Cougar Only:
A. Locate the hardshell connector in the coolant sensor switch circuit connecting the 19D605/ 18C619 harness to the 19D887 harness (Figure 8).
B. Disconnect the hardshell connector (Figure 8) and remove and discard the (E6SZ-19D887-A) harness.
C. Connect a new jumper harness (E6SZ-19D887-B) to the 19D605/18C619 harness hardshell connector and route the new harness to the coolant temperature switch installed in Step 4.
D. Connect the new harness to the coolant temperature switch and attach the eyelet terminal of the harness to an available drill dimple on the cowl with a No. 8 drill point screw (381801-S36B).
E. Fill the coolant system and run the engine to check for coolant leaks. Then, add coolant to the cooling system as necessary.
F. Check the EATC system for proper operation, including the cold engine blower lock-out function.
PART NUMBER PART NAME CLASS
E4DZ-18472-D Inlet Hose - Heater C
E4DZ-18472-A Inlet Hose - Heater C
E5SZ-18B402-A Tube Assembly C
E6LY-18472-C Return Hose - Heater C
E6LY-19D570-A Jumper Wire C
E6FZ-14488-A Splice Clip C
381801-S36B No. 8 Drill Point Screw S
C9AZ-8287-A Hose Clamp AG
E5SZ-18D371-A Switch Assembly B
E6SZ-19D887-A Jumper Harness C
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
OPERATION: SP18371A86
TIME: 0.5 Hr. DLR. CODING: Basic Part No. 18B402 - Code: 42