Heater Core: Service and Repair

Fig. 33 Heater Assembly. Models Less A/C Except Horizon & Omni:

Fig. 34 Heater Assembly:

Disable airbag, refer to Air Bags and Seat Belts/Air Bags (Supplemental Restraint Systems)/Service and Repair. After procedure has been completed, rearm airbag system.

1. Disconnect battery ground cable, then discharge refrigerant from A/C system and disconnect lines from evaporator heater assembly.
2. Drain cooling system, then disconnect and plug heater hoses from evaporator heater assembly.
3. Remove A/C condensate drain and disconnect vacuum lines.
4. On Acclaim and Spirit models, remove H-valve from evaporator plate.
5. On Dynasty, LeBaron and New Yorker models, remove right upper and lower underpanel silencers.
6. On LeBaron models with passive restraint system, remove right lower trim panel.
7. On Acclaim, Dynasty, Lancer, LeBaron GTS, New Yorker, Shadow, Spirit and Sundance models, remove steering column cover.
8. On Daytona and LeBaron models with passive restraint system, remove outer steering column cover.
9. On Acclaim, Dynasty, New Yorker, Spirit models and LeBaron models with passive restraint system, remove left underpanel silencer.
10. On Acclaim and Spirit models, remove right underpanel silencer pad.
11. On Daytona and LeBaron models with passive restraint system, remove hood release and parking brake release handles from inner steering column cover, then remove the cover.
12. On all models, slide front bench seat or right front bucket seat back as far as possible.
13. On Acclaim, Shadow, Spirit and Sundance models, remove right A-pillar trim.
14. On all models, remove right cowl side trim. On LeBaron models, unfasten lower end of right A-pillar trim to allow removal of side trim.
15. Remove glove box. If necessary, remove right instrument panel reinforcement to allow glove box removal.
16. On Acclaim and Spirit models, proceed as follows:
a. Disconnect vacuum lines from air door actuator and electrical connector from blower motor.
b. Remove relay panel from above glove compartment opening, then disconnect A/C vacuum line connector and radio noise capacitors.
c. Remove left windshield pillar trim cover and left lower side cowl side trim cover.
d. Remove hood release handle mechanism attaching screws, then disconnect parking brake release mechanism connecting rod.
e. Remove Instrument center bezel, then the radio and heater controls.
f. Remove cigar lighter and message center/trip computer, if equipped.
17. On Daytona and LeBaron models, proceed as follows:
a. Remove forward console bezel, side trim and lower carpet panels.
b. Loosen floor console and move rearward, then remove forward console.
c. On models with passive restraint system, remove instrument panel-to-floor reinforcement.
18. On Shadow and Sundance models, proceed as follows:
a. Remove center bezel, then the lower center module cover.
b. Remove floor console, then the instrument panel brace from steering column opening.
c. Remove instrument panel support bracket from below glove box opening.
d. Remove ashtray, then the radio assembly and panel top cover.
e. Remove three right side instrument panel attaching screws below windshield.
19. On Aries and Reliant models, remove floor console.
20. On Lancer and LeBaron GTS models, remove front and rear consoles.
21. On Dynasty and New Yorker models, remove ashtray assembly.
22. On Aries, Reliant, Shadow and Sundance models, pull lower right side of instrument panel rearward.
23. On all models, remove center distribution and defroster adapter ducts.
24. On Dynasty, Lancer, LeBaron GTS, New Yorker, Shadow and Sundance models, disconnect relay module electrical connector.
25. On Shadow and Sundance models, remove instrument panel-to-evaporator heater assembly bracket, then the lower air distribution duct.
26. On Aries and Reliant, remove audible message center, then the brace securing right side cowl to plenum.
27. On all models, disconnect blower motor electrical connector, then the demister hoses from top of evaporator heater assembly.
28. On models less automatic temperature control, proceed as follows:
a. Disconnect temperature control cable flag from bottom of evaporator heater assembly.
b. Unfasten cable from left side of heat distribution duct.
c. Disconnect vacuum lines from evaporator heater assembly.
29. On models with automatic temperature control, disconnect instrument panel wiring harness from rear of ATC unit.
30. On Dynasty, Lancer, LeBaron GTS and New Yorker models, disconnect fuse block and right 25-way connector from instrument panel.
31. On Acclaim and Spirit models, proceed as follows:
a. Remove steering column attaching bolts and allow steering wheel to rest on front seat, then remove upper instrument panel defroster cover.
b. Remove upper instrument panel attaching screws under windshield opening, then loosen left lower instrument panel attaching screw and remove right instrument panel attaching screw.
32. On all models, unfasten antenna cable from clip on evaporator heater assembly.
33. On all models except Dynasty, Lancer, LeBaron GTS and New Yorker, fold carpet back from right side of floor.
34. On all models, remove four evaporator heater assembly attaching nuts from engine compartment side.
35. Remove lower screw from hanger strap, then rotate the strap aside.
36. Pull evaporator heater assembly rearward until mounting studs are cleared, then lower unit, Figs. 33 and 34.
37. On Shadow and Sundance models, remove demister adapter from top of unit.
38. On Shadow and Sundance models, slide assembly up from under instrument panel while pulling lower right side of panel rearward.
39. On all models except Acclaim, Shadow, Spirit and Sundance, pull lower right side of instrument panel rearward and rotate assembly while pulling from under instrument panel.
40. On all models, place evaporator heater unit on bench, then remove evaporator heater unit top cover.
41. Remove expansion valve seal and retaining screw from under sealing plate, then lift heater core out of assembly.
42. Reverse procedure to install.