is an International Standards Organization (ISO)-
type relay (Fig. 1). Relays conforming to the ISO
specifications have common physical dimensions, cur-
rent capacities, terminal functions and patterns. The
rear A/C clutch relay is an electromechanical device
that uses a low current input controlled by the rear
A/C control module to control the high current output
to the A/C clutch field coil for the rear A/C system.

The rear A/C clutch relay is located in the relay

block in the rear A/C evaporator housing.

24 - 24

CONTROLS - REAR

OPERATION

The ISO-standard rear A/C clutch relay is an elec-

tromechanical switch that uses a low current input
from the rear A/C control module to control the high
current output to the rear A/C clutch. The movable,
common feed relay contact is held against the fixed,
normally closed relay contact by spring pressure.
When the electromagnetic relay coil is energized, it
draws the movable common feed relay contact away
from the fixed, normally closed relay contact and,
holds it against the fixed, normally open relay con-
tact. This action allows high current to flow to the
A/C clutch field coil.

When the relay coil is de-energized, spring pres-

sure returns the movable relay contact back against
the fixed, normally closed contact point. The resistor
or diode is connected in parallel with the relay coil,
and helps to dissipate voltage spikes and electromag-
netic interference that can be generated as the elec-
tromagnetic field of the relay coil collapses.

The rear A/C clutch relay terminals are connected

to the vehicle electrical system through a receptacle
in the relay block located in the rear A/C evaporator
housing.

The rear A/C clutch relay cannot be repaired and,

if faulty or damaged, it must be replaced. Refer to
the appropriate wiring information for diagnosis and
testing of the ISO-standard relay and for complete
HVAC wiring diagrams.

REMOVAL

(1) Disconnect and isolate the negative battery

cable.

(2) Remove the air filter from the rear A/C evapo-

rator housing (Refer to 24 - HEATING & AIR CON-

DITIONING/DISTRIBUTION - REAR/AIR FILTER -
REMOVAL).

(3) Reach up into the rear A/C evaporator housing

and remove the rear A/C clutch relay from the relay
block (Fig. 2).

Fig. 1 Rear A/C Clutch Relay

1 - STANDARD ISO RELAY
2 - TERMINAL PATTERN

CONTROLS - REAR

24 - 25

INSTALLATION

(1) Position the rear A/C clutch relay into the

proper receptacle of the relay block located in the
rear A/C evaporator housing.

(2) Align the A/C clutch relay terminals with the

terminal cavities in the relay block receptacle and
push down firmly on the relay until the terminals
are fully seated.

(3) Install the rear air filter (Refer to 24 - HEAT-

ING

AIR

CONDITIONING/DISTRIBUTION

REAR/AIR FILTER - INSTALLATION).

(4) Reconnect the negative battery cable.

A / C CONDENSER FAN RELAY

DESCRIPTION

The rear A/C condenser fan relay for the rear A/C

system is an International Standards Organization
(ISO)-type relay (Fig. 3). Relays conforming to the
ISO specifications have common physical dimensions,
current capacities, terminal functions and patterns.
The rear A/C condenser fan relay is an electrome-
chanical device that uses a low current input to con-
trol the high current output to the A/C condenser fan
for the rear heating-A/C system.

The rear A/C condenser fan relay is located in the

relay block in the rear A/C evaporator housing.

OPERATION

The ISO-standard rear A/C condenser fan relay is

an electromechanical switch that uses a low current
input from the rear A/C control module to control the
high current output to the rear A/C condenser cooling
fan. The movable, common feed relay contact is held
against the fixed, normally closed relay contact by
spring pressure. When the electromagnetic relay coil

Fig. 2 Rear A/C Clutch Relay

1 - REAR A/C EVAPORATOR HOUSING
2 - BLOWER MOTOR RELAY K204
3 - BLOWER MOTOR RELAY K203

4 - BLOWER MOTOR RELAY K201
5 - REAR CONDENSER FAN RELAY K205
6 - REAR COMPRESSOR RELAY K206

Fig. 3 Rear A/C Condenser Fan Relay

1 - STANDARD ISO RELAY
2 - TERMINAL PATTERN

24 - 26

CONTROLS - REAR

is energized, it draws the movable common feed relay
contact away from the fixed, normally closed relay
contact and, holds it against the fixed, normally open
relay contact. This action allows high current to flow
to the electric cooling fan motor.

When the relay coil is de-energized, spring pres-

The rear A/C condenser fan relay terminals are

connected to the vehicle electrical system through a
receptacle in the relay block located in the rear A/C
evaporator housing.

The rear A/C condenser fan relay cannot be

repaired and, if faulty or damaged, it must be
replaced. Refer to the appropriate wiring information
for diagnosis and testing of the ISO-standard relay
and for complete HVAC wiring diagrams.

REMOVAL

(1) Disconnect and isolate the negative battery

cable.

(2) Remove the air filter from the rear A/C evapo-

rator housing (Refer to 24 - HEATING & AIR CON-
DITIONING/DISTRIBUTION - REAR/AIR FILTER -
REMOVAL).

(3) Reach up into the rear A/C evaporator housing

and remove the rear A/C condenser fan relay from
the relay block (Fig. 4).

CONTROLS - REAR

24 - 27

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