Mazda MX-5 Miata (1997+). Manual — part 77

6. Turn ignition blower switch off. Backprobe Blue/White wire terminal, Blue/Red wire terminal,

Blue/Green wire terminal and Blue/Yellow wire terminal of blower switch connector If battery voltage is
not present, repair open wire(s) between blower resistor and blower switch. If battery voltage exists,
check blower motor.

BLOWER MOTOR

Disconnect blower motor 2-pin connector from bottom of blower case. Apply battery voltage across blower
motor terminals. Replace blower motor if it does not operate.

BLOWER RESISTOR

Disconnect blower resistor connectors from blower case. Check continuity, in turn, between Blue wire terminal
of 1-pin connector and each terminal of 4-pin connector. Ensure continuity exists. Replace resistor if continuity
does not exist.

BLOWER SWITCH

Disconnect blower switch connector. Place blower switch in indicated positions, and check continuity between
specified blower switch terminals. See BLOWER SWITCH TEST table. See Fig. 2 . If continuity is not as
specified, replace blower switch.

BLOWER SWITCH TEST

Switch Position

Continuity Between Terminals

Off

(1)

Low

"A" & "G"

Medium-Low

"C", "G" & "H"

Medium-High

"E", "G" & "H"

High

"B", "G" & "H"

(1)

There should not be continuity between any terminals.

1997 Mazda MX-5 Miata

HEATER SYSTEM 1997 Heater System

Fig. 2: Identifying Blower Switch Terminals
Courtesy of MAZDA MOTORS CORP.

REMOVAL & INSTALLATION

BLOWER UNIT

Removal & Installation

Remove glove box. Disconnect electrical connectors. Loosen seal plate between blower unit and evaporator unit
(if equipped). Remove blower unit bolts and blower unit. Disassemble blower unit to remove blower motor and
blower resistor. To install, reverse removal procedure.

CONTROL PANEL

Removal & Installation

Remove rear center console. Remove vent outlets from center panel. Remove center panel. Remove control
panel screws, and pull control panel from center panel. Disconnect heater control cables. To install, reverse
removal procedure.

HEATER CORE

Removal & Installation

WARNING:

To avoid injury from accidental air bag deployment, read and follow all
SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR BAG
SYSTEM procedures in AIR BAG RESTRAINT SYSTEM article in the
ACCESSORIES/SAFETY EQUIPMENT section.

1997 Mazda MX-5 Miata

HEATER SYSTEM 1997 Heater System

Drain coolant. Disconnect heater hoses at engine compartment firewall. Remove grommets from holes (if
equipped). Remove instrument panel. See INSTRUMENT PANEL . Remove heater unit. Disassemble heater
unit to remove heater core. See Fig. 1 . To install, reverse removal procedure. Fill cooling system.

INSTRUMENT PANEL

Removal & Installation

Before disconnecting negative battery cable, obtain radio anti-theft code from vehicle owner. Disconnect
negative battery cable. Remove components in the order listed in illustration. See Fig. 3 . To install, reverse
removal procedure.

Fig. 3: Exploded View Of Instrument Panel
Courtesy of MAZDA MOTORS CORP.

WIRING DIAGRAM

1997 Mazda MX-5 Miata

HEATER SYSTEM 1997 Heater System

1997 Mazda MX-5 Miata

HEATER SYSTEM 1997 Heater System