Acura TSX / Honda Accord CL. Manual - part 400

Courtesy of AMERICAN HONDA MOTOR CO., INC.

RADIATOR FAN SWITCH CIRCUIT TROUBLE SHOOTING (OPEN) 

1. Disconnect the radiator fan switch 2-pin connector. Turn the ignition switch ON. Measure voltage 

between radiator fan switch 2-pin connector, terminal No. 2 and body ground. See Fig. 4 . If there is 
battery voltage, go to next step. If battery voltage is not present, repair open in the wire between radiator 
fan switch 2-pin connector, terminal No. 2 and under-hood fuse/relay box.  

2. Turn the ignition switch OFF, and check for continuity between radiator fan switch 2-pin connector, 

terminal No. 1 and body ground. See Fig. 4 . If there is continuity, replace the radiator fan switch. See 
RADIATOR FAN SWITCH under REMOVAL & INSTALLATION. If there is no continuity, check 
for an open in the wire between radiator fan switch 2-pin connector, terminal No. 1 and body ground. If 
the wire is OK, check for a poor ground at G301.  

RADIATOR FAN SWITCH CIRCUIT TROUBLE SHOOTING (SHORT) 

1. Remove the radiator fan relay from the under-hood fuse/relay box, and test it. See FAN RELAYS under 

COMPONENT TESTS. If the relay is OK, go to next step. If the relay is not OK, replace the radiator fan 
relay.  

2. Remove the radiator fan switch, and test it. See RADIATOR FAN SWITCH under COMPONENT 

TESTS. If the radiator fan switch is OK, go to next step. If the radiator fan switch is not OK, replace the 
radiator fan switch. See RADIATOR FAN SWITCH under REMOVAL & INSTALLATION.  

3. Disconnect the under-hood fuse relay box 20-pin connector. Check for continuity between radiator fan 

switch 2-pin connector, terminal No. 2 and. body ground. See Fig. 4 . If there is continuity, repair short in 
the wire between radiator fan switch 2-pin connector, terminal No. 2 and under-hood fuse/relay box. If 
there is no continuity, replace the under-hood fuse/relay box.  

COMPONENT TESTS 

FAN MOTOR 

Disconnect appropriate fan motor connector. Apply battery voltage and ground between fan motor terminals. If 
fan motor operates, check related components and wiring. If fan motor does not operate, reverse battery leads. If 
fan still does not operate, replace fan motor. See COOLING FANS under REMOVAL & INSTALLATION. 

FAN RELAYS 

1. Although physical appearance of relays may be different, basic relay operation is similar. Remove relay 

to be tested. Check continuity between relay terminals No. 1 and 3. See WIRING DIAGRAMS . 
Continuity should not exist.  

2. Apply battery voltage between terminals No. 2 and 4. Continuity should exist between terminals No. 1 

and 3. If continuity is not as specified, replace relay.  

RADIATOR FAN SWITCH 

1. Remove the radiator fan switch from the radiator. Suspend the radiator fan switch in a container of water. 

 

2004 Acura TSX 

2004 ENGINE COOLING Electric Cooling Fans - TSX

  

 

See Fig. 5 .  

2. Heat the water, and check the temperature with a thermometer. Do not let the thermometer touch the 

bottom of the hot container. Measure the continuity between terminal "A" and terminal "B" according to 
RADIATOR FAN SWITCH CONTINUITY SPECIFICATIONS .  

RADIATOR FAN SWITCH CONTINUITY SPECIFICATIONS 

Fig. 5: Testing Radiator Fan Switch 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

REMOVAL & INSTALLATION 

COOLING FANS 

Application

(1)

 Temperature - °F (°C)

Switch

196-203 (91-95)

(1)

Switch opens when temperature drops to 5-15°F (3-8°C) less than continuity temperature.

 

2004 Acura TSX 

2004 ENGINE COOLING Electric Cooling Fans - TSX

  

 

Removal & Installation 

For removal and installation, see Fig. 6 . 

Fig. 6: Removing Cooling Fans 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

RADIATOR FAN SWITCH 

Removal & Installation 

 

2004 Acura TSX 

2004 ENGINE COOLING Electric Cooling Fans - TSX

  

 

1. Drain the engine coolant.  

2. Remove the splash shield.  

3. Disconnect the radiator fan switch connector, then remove the radiator fan switch. See Fig. 7 .  

4. Install the radiator fan switch with a new "O" ring.  

5. Refill the radiator with engine coolant, and bleed air from the cooling system with the heater valve open.  

Fig. 7: Removing Radiator Fan Switch 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

WIRING DIAGRAMS 

 

2004 Acura TSX 

2004 ENGINE COOLING Electric Cooling Fans - TSX