Thermistor Probe Servicing
FIGURE 3:
1. Remove the 4WD Selection Switch mounting screws (A) and lower the switch housing (Fig. 3).
FIGURE 4:
2. Remove the lower evaporator housing mounting screws (B) (Fig. 4).
FIGURE 5:
3. Lower the evaporator housing (C) (Fig. 5).
FIGURE 6:
This will give access to the evaporator housing cover (D) (Fig. 6).
FIGURE 7:
4. Remove the insulation material (E) (Fig. 7).
FIGURE 8:
5. Remove the mounting screws (F) retaining the evaporator housing cover (Fig. 8). Remove the evaporator housing cover (D).
WARNING: Be sure to perform the following operation with great care. Should the drill bit accidently penetrate the evaporator core, the freon gas will escape very rapidly. This will discharge the A/C system and may result in personal bodily injury.
FIGURE 9:
6. Place a piece of sheet metal (G) between the evaporator core (H) and the front of the evaporator housing (Fig. 9).
NOTE: This piece of sheet metal will serve to protect the evaporator core from any accidental damage from the drill bit.
FIGURE 10:
NOTE: The outer edge of the hole (J) must be kept within 3 mm (1/8 in.) of the black metal bracket (K), and, within 3 mm (1/8 in.) of the vertical indentation (L).
7. Drill a 31.75 mm (1 1/4 in.) hole (J) through the front of the evaporator housing (Fig. 10).
8. Trim the edges of the hole to protect the thermistor probe from possible damage when it is installed later.
FIGURE 11:
9. Remove the blower motor mounting screws
(M) (Fig. 11).
FIGURE 12:
10. Remove the blower motor (N) (Fig. 12). This will give access to the evaporator mounting screws.
FIGURE 13:
11. Remove the evaporator core mounting screws (P) (Fig. 13).
FIGURE 14:
12. Disconnect the electrical harness connector
(R) (Fig. 14).
13. Lift the evaporator core partially out of the evaporator housing to gain access to the thermistor probe.
FIGURE 15:
14. Remove the thermistor probe (S) through the hole (J) which was cut out earlier (Fig. 15).
15. Install the replacement thermistor probe, P/N 8956 002 728, through the hole (J).
NOTE: If it is not possible to put the replacement probe into the same hole left by the defective probe, then, be sure to position the replacement thermistor probe into the evaporator housing as low and as far to the left as possible.
16. Install the plastic grommet, P/N 8956 001 959, in the hole drilled earlier.
17. Lower the evaporator core into the housing.
FIGURE 16:
18. Route the wires (T) from the replacement thermistor probe between the evaporator housing and the evaporator unit as shown (Fig. 16).
FIGURE 17:
19. Connect the thermistor connector to the electrical harness connector (Fig. 17).
FIGURE 18:
20. Position the evaporator core and secure it with the mounting screws (P) (Fig. 18).
21. Install the blower motor.
22. Install the evaporator housing cover.
23. Install the insulation.
24. Position the evaporator housing and secure it with the mounting screws.
FIGURE 19:
25. Attach the ground wire (U) with mounting screw (V) (Fig. 19).
26. Position the 4WD Selection Switch and secure it with mounting screws.
27. Start the engine.
28. Activate the A/C system.
29. Inspect to verify that the A/C system is operating properly, and, that the evaporator icing condition has been eliminated.
PARTS INFORMATION
DESCRIPTION QUANTITY PART NUMBER
TEMPERATURE CONTROL MODULE 1 8956 001 959
THERMISTOR PROBE (Thermo Couple) 1 8956 002 728
PLASTIC GROMMET 1 8956 001 959
SRT/TIC INFORMATION
OPERATION DESCRIPTION OPERATION TIME TIC SUPPLIER
NUMBER CODE
CO. TEMPERATURE CONTROL MODULE 6726 0.2 6-242 708,755
- REPLACE (Inc. Inspection)
CO. THERMISTOR PROBE - REPLACE 0607 0.7 6-242 708,733
SUPPLIERS: 708 Robert Shaw 755 American Air
FILING INSTRUCTIONS
Record this I.S. Note on page L-28 of M.R. 253 and file it in the binder.
Discard the previous M.R. 253 I.S. Note 12E (Rev.), P/N 8980 001 350.