Cooling Fan Circuit
FA20 COOLING: COOLING FAN SYSTEM: Cooling Fan Circuit; 2013 MY FR-S [03/2012 -]
- Cooling Fan Circuit
DESCRIPTION
The ECM turns on or off the fan relays using signals calculated from the engine coolant temperature, air conditioning (ON/OFF), air conditioner refrigerant pressure, engine speed and vehicle speed signals.
The ECM switches the circuit of the cooling fan motors between series and parallel by turning on or off the fan relays in order to control the speed of the cooling fan motors in two steps.
WIRING DIAGRAM
Refer to System Diagram Description and Operation.
INSPECTION PROCEDURE
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
1. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE ELECTRIC COOLING FAN)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Active Test / Control the Electric Cooling Fan.
(e) Check the operation of the cooling fans while operating them using the Techstream.
OK:
NG -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures
OK -- Continue to next step.
2. INSPECT ENGINE ROOM RELAY BLOCK (FAN NO. 1 RELAY VOLTAGE)
(a) Remove the FAN No. 1 relay from the engine room relay block.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
(c) Reinstall the FAN No. 1 relay.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - FAN NO. 1 RELAY)
OK -- Continue to next step.
3. INSPECT ENGINE ROOM RELAY BLOCK (FAN NO. 3 RELAY VOLTAGE)
(a) Remove the FAN No. 3 relay from the engine room relay block.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
(c) Reinstall the FAN No. 3 relay.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - FAN NO. 3 RELAY)
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (FAN NO. 1, NO. 2 OR NO. 3 RELAY)
(a) Remove the FAN No. 1, FAN No. 2 and FAN No. 3 relays from the engine room relay block.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
(d) Reinstall the FAN No. 1, FAN No. 2 and FAN No. 3 relay.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 1, NO. 2 OR NO. 3 RELAY)
OK -- Continue to next step.
5. INSPECT FAN NO. 1 RELAY
(a) Inspect the FAN No. 1 relay Testing and Inspection.
NG -- REPLACE FAN NO. 1 RELAY
OK -- Continue to next step.
6. INSPECT FAN NO. 2 RELAY
(a) Inspect the FAN No. 2 relay Testing and Inspection.
NG -- REPLACE FAN NO. 2 RELAY
OK -- Continue to next step.
7. INSPECT FAN NO. 3 RELAY
(a) Inspect the FAN No. 3 relay Testing and Inspection.
NG -- REPLACE FAN NO. 3 RELAY
OK -- Continue to next step.
8. CHECK HARNESS AND CONNECTOR (FAN NO. 2 RELAY - BODY GROUND)
(a) Remove the FAN No. 2 relay from the engine room relay block.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
(c) Reinstall the FAN No. 2 relay.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 2 RELAY - BODY GROUND)
OK -- Continue to next step.
9. INSPECT COOLING FAN MOTOR
(a) Inspect the cooling fan motor Testing and Inspection.
NG -- REPLACE COOLING FAN MOTOR Removal
OK -- Continue to next step.
10. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR - BODY GROUND)
(a) Disconnect the A45 cooling fan motor connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
(c) Reconnect the A45 cooling fan motor connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR - BODY GROUND)
OK -- Continue to next step.
11. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR - ENGINE ROOM RELAY BLOCK)
(a) Disconnect the A45 cooling fan motor connector.
(b) Remove the FAN No. 1 and FAN No. 2 relays from the engine room relay block.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
Standard Resistance (Check for Short):
(d) Reconnect the A45 cooling fan motor connector.
(e) Reinstall the FAN No. 1 and FAN No. 2 relays.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR - ENGINE ROOM RELAY BLOCK)
OK -- Continue to next step.
12. INSPECT NO. 2 COOLING FAN MOTOR
(a) Inspect the No. 2 cooling fan motor Testing and Inspection.
NG -- REPLACE NO. 2 COOLING FAN MOTOR Removal
OK -- Continue to next step.
13. CHECK HARNESS AND CONNECTOR (NO. 2 COOLING FAN MOTOR - ENGINE ROOM RELAY BLOCK)
(a) Disconnect the A46 No. 2 cooling fan motor connector.
(b) Remove the FAN No. 2 and FAN No. 3 relays from the engine room relay block.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
Standard Resistance (Check for Short):
(d) Reconnect the A46 No. 2 cooling fan motor connector.
(e) Reinstall the FAN No. 2 and FAN No. 3 relays.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 2 COOLING FAN MOTOR - ENGINE ROOM RELAY BLOCK)
OK -- Continue to next step.
14. INSPECT ENGINE ROOM RELAY BLOCK (FAN NO. 1 RELAY - FAN NO. 2 RELAY)
(a) Remove the FAN No. 1 and FAN No. 2 relays from the engine room relay block.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
Standard Resistance (Check for Short):
(c) Reinstall the FAN No. 1 and FAN No. 2 relays.
NG -- REPLACE ENGINE ROOM RELAY BLOCK
OK -- Continue to next step.
15. CHECK HARNESS AND CONNECTOR (ECM - ENGINE ROOM RELAY BLOCK)
(a) Disconnect the A35 ECM connector.
(b) Remove the FAN No. 2 and FAN No. 3 relays from the engine room relay block.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
Standard Resistance (Check for Short):
(d) Reconnect the A35 ECM connector.
(e) Reinstall the FAN No. 2 and FAN No. 3 relays.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - ENGINE ROOM RELAY BLOCK)
OK -- REPLACE ECM Removal